- Fix bugs on unexpected IMAP connection close (#1486190, #1486270)

- Iloha's imap.inc rewritten into rcube_imap_generic class
- rcube_imap code re-formatting

1 files changed, 3248 insertions, 3282 deletions

diff --git a/program/include/rcube_imap.php b/program/include/rcube_imap.php
index 24080d618..b1f9132c5 100644
--- a/program/include/rcube_imap.php
+++ b/program/include/rcube_imap.php
@@ -9,11 +9,11 @@
  | Licensed under the GNU GPL                                            |
  |                                                                       |
  | PURPOSE:                                                              |
- |   IMAP wrapper that implements the Iloha IMAP Library (IIL)           |
- |   See http://ilohamail.org/ for details                               |
+ |   IMAP Engine                                                         |
  |                                                                       |
  +-----------------------------------------------------------------------+
  | Author: Thomas Bruederli <roundcube@gmail.com>                        |
+ | Author: Aleksander Machniak <alec@alec.pl>                            |
  +-----------------------------------------------------------------------+
 
  $Id$
@@ -21,10 +21,6 @@
 */
 
 
-/*
- * Obtain classes from the Iloha IMAP library
- */
-require_once('lib/imap.inc');
 require_once('lib/mime.inc');
 require_once('lib/tnef_decoder.inc');
 
@@ -32,3730 +28,3700 @@ require_once('lib/tnef_decoder.inc');
 /**
  * Interface class for accessing an IMAP server
  *
- * This is a wrapper that implements the Iloha IMAP Library (IIL)
- *
  * @package    Mail
  * @author     Thomas Bruederli <roundcube@gmail.com>
- * @version    1.5
- * @link       http://ilohamail.org
+ * @version    1.6
  */
 class rcube_imap
 {
-  public $debug_level = 1;
-  public $error_code = 0;
-  public $skip_deleted = false;
-  public $root_dir = '';
-  public $page_size = 10;
-  public $list_page = 1;
-  public $delimiter = NULL;
-  public $threading = false;
-  public $fetch_add_headers = '';
-  public $conn;
-
-  private $db;
-  private $root_ns = '';
-  private $mailbox = 'INBOX';
-  private $sort_field = '';
-  private $sort_order = 'DESC';
-  private $caching_enabled = false;
-  private $default_charset = 'ISO-8859-1';
-  private $struct_charset = NULL;
-  private $default_folders = array('INBOX');
-  private $default_folders_lc = array('inbox');
-  private $icache = array();
-  private $cache = array();
-  private $cache_keys = array();  
-  private $cache_changes = array();
-  private $uid_id_map = array();
-  private $msg_headers = array();
-  public  $search_set = NULL;
-  public  $search_string = '';
-  private $search_charset = '';
-  private $search_sort_field = '';
-  private $search_threads = false;
-  private $db_header_fields = array('idx', 'uid', 'subject', 'from', 'to', 'cc', 'date', 'size');
-  private $options = array('auth_method' => 'check');
-  private $host, $user, $pass, $port, $ssl;
-
-
-  /**
-   * Object constructor
-   *
-   * @param object DB Database connection
-   */
-  function __construct($db_conn)
-    {
-    $this->db = $db_conn;
-    }
-
-
-  /**
-   * Connect to an IMAP server
-   *
-   * @param  string   Host to connect
-   * @param  string   Username for IMAP account
-   * @param  string   Password for IMAP account
-   * @param  number   Port to connect to
-   * @param  string   SSL schema (either ssl or tls) or null if plain connection
-   * @return boolean  TRUE on success, FALSE on failure
-   * @access public
-   */
-  function connect($host, $user, $pass, $port=143, $use_ssl=null)
-    {
-    global $ICL_SSL, $ICL_PORT, $IMAP_USE_INTERNAL_DATE;
-    
-    // check for Open-SSL support in PHP build
-    if ($use_ssl && extension_loaded('openssl'))
-      $ICL_SSL = $use_ssl == 'imaps' ? 'ssl' : $use_ssl;
-    else if ($use_ssl) {
-      raise_error(array('code' => 403, 'type' => 'imap',
-        'file' => __FILE__, 'line' => __LINE__,
-        'message' => "Open SSL not available"), true, false);
-      $port = 143;
-    }
-
-    $ICL_PORT = $port;
-    $IMAP_USE_INTERNAL_DATE = false;
-
-    $attempt = 0;
-    do {
-      $data = rcmail::get_instance()->plugins->exec_hook('imap_connect', array('host' => $host, 'user' => $user, 'attempt' => ++$attempt));
-      if (!empty($data['pass']))
-        $pass = $data['pass'];
-
-      $this->conn = iil_Connect($data['host'], $data['user'], $pass, $this->options);
-    } while(!$this->conn && $data['retry']);
-
-    $this->host = $data['host'];
-    $this->user = $data['user'];
-    $this->pass = $pass;
-    $this->port = $port;
-    $this->ssl = $use_ssl;
-    
-    // print trace messages
-    if ($this->conn && ($this->debug_level & 8))
-      console($this->conn->message);
-    
-    // write error log
-    else if (!$this->conn && $GLOBALS['iil_error'])
-      {
-      $this->error_code = $GLOBALS['iil_errornum'];
-      raise_error(array('code' => 403, 'type' => 'imap',
-        'file' => __FILE__, 'line' => __LINE__,
-        'message' => $GLOBALS['iil_error']), true, false);
-      }
-
-    // get server properties
-    if ($this->conn)
-      {
-      if (!empty($this->conn->rootdir))
-        $this->set_rootdir($this->conn->rootdir);
-      if (empty($this->delimiter))
-	$this->get_hierarchy_delimiter();
-      }
-
-    return $this->conn ? true : false;
-    }
-
-
-  /**
-   * Close IMAP connection
-   * Usually done on script shutdown
-   *
-   * @access public
-   */
-  function close()
+    public $debug_level = 1;
+    public $error_code = 0;
+    public $skip_deleted = false;
+    public $root_dir = '';
+    public $page_size = 10;
+    public $list_page = 1;
+    public $delimiter = NULL;
+    public $threading = false;
+    public $fetch_add_headers = '';
+    public $conn; // rcube_imap_generic object
+
+    private $db;
+    private $root_ns = '';
+    private $mailbox = 'INBOX';
+    private $sort_field = '';
+    private $sort_order = 'DESC';
+    private $caching_enabled = false;
+    private $default_charset = 'ISO-8859-1';
+    private $struct_charset = NULL;
+    private $default_folders = array('INBOX');
+    private $icache = array();
+    private $cache = array();
+    private $cache_keys = array();  
+    private $cache_changes = array();
+    private $uid_id_map = array();
+    private $msg_headers = array();
+    public  $search_set = NULL;
+    public  $search_string = '';
+    private $search_charset = '';
+    private $search_sort_field = '';
+    private $search_threads = false;
+    private $db_header_fields = array('idx', 'uid', 'subject', 'from', 'to', 'cc', 'date', 'size');
+    private $options = array('auth_method' => 'check');
+    private $host, $user, $pass, $port, $ssl;
+
+
+    /**
+     * Object constructor
+     *
+     * @param object DB Database connection
+     */
+    function __construct($db_conn)
+    {
+        $this->db = $db_conn;
+        $this->conn = new rcube_imap_generic();
+    }
+
+
+    /**
+     * Connect to an IMAP server
+     *
+     * @param  string   Host to connect
+     * @param  string   Username for IMAP account
+     * @param  string   Password for IMAP account
+     * @param  number   Port to connect to
+     * @param  string   SSL schema (either ssl or tls) or null if plain connection
+     * @return boolean  TRUE on success, FALSE on failure
+     * @access public
+     */
+    function connect($host, $user, $pass, $port=143, $use_ssl=null)
+    {
+        // check for Open-SSL support in PHP build
+        if ($use_ssl && extension_loaded('openssl'))
+            $this->options['ssl_mode'] = $use_ssl == 'imaps' ? 'ssl' : $use_ssl;
+        else if ($use_ssl) {
+            raise_error(array('code' => 403, 'type' => 'imap',
+                'file' => __FILE__, 'line' => __LINE__,
+                'message' => "OpenSSL not available"), true, false);
+            $port = 143;
+        }
+
+        $this->options['port'] = $port;
+
+        $attempt = 0;
+        do {
+            $data = rcmail::get_instance()->plugins->exec_hook('imap_connect',
+                array('host' => $host, 'user' => $user, 'attempt' => ++$attempt));
+            
+            if (!empty($data['pass']))
+                $pass = $data['pass'];
+
+            $this->conn->connect($data['host'], $data['user'], $pass, $this->options);
+        } while(!$this->conn->connected() && $data['retry']);
+
+        $this->host = $data['host'];
+        $this->user = $data['user'];
+        $this->pass = $pass;
+        $this->port = $port;
+        $this->ssl  = $use_ssl;
+
+        // print trace messages
+        if ($this->conn->connected()) {
+            if ($this->conn->message && ($this->debug_level & 8)) {
+                console($this->conn->message);
+            }
+
+            // get server properties
+            if (!empty($this->conn->rootdir))
+                $this->set_rootdir($this->conn->rootdir);
+            if (empty($this->delimiter))
+	            $this->get_hierarchy_delimiter();
+        }
+        // write error log
+        else if ($this->conn->error) {
+            $this->error_code = $this->conn->errornum;
+            raise_error(array('code' => 403, 'type' => 'imap',
+                'file' => __FILE__, 'line' => __LINE__,
+                'message' => $this->conn->error), true, false);
+        }
+
+        return $this->conn ? true : false;
+    }
+
+
+    /**
+     * Close IMAP connection
+     * Usually done on script shutdown
+     *
+     * @access public
+     */
+    function close()
     {    
-    if ($this->conn)
-      iil_Close($this->conn);
+        if ($this->conn && $this->conn->connected())
+            $this->conn->close();
+        $this->write_cache();
     }
 
 
-  /**
-   * Close IMAP connection and re-connect
-   * This is used to avoid some strange socket errors when talking to Courier IMAP
-   *
-   * @access public
-   */
-  function reconnect()
+    /**
+     * Close IMAP connection and re-connect
+     * This is used to avoid some strange socket errors when talking to Courier IMAP
+     *
+     * @access public
+     */
+    function reconnect()
     {
-    $this->close();
-    $this->connect($this->host, $this->user, $this->pass, $this->port, $this->ssl);
+        $this->close();
+        $this->connect($this->host, $this->user, $this->pass, $this->port, $this->ssl);
     
-    // issue SELECT command to restore connection status
-    if ($this->mailbox)
-      iil_C_Select($this->conn, $this->mailbox);
+        // issue SELECT command to restore connection status
+        if ($this->mailbox)
+            $this->conn->select($this->mailbox);
     }
 
-  /**
-   * Set options to be used in iil_Connect()
-   */
-  function set_options($opt)
-  {
-    $this->options = array_merge($this->options, (array)$opt);
-  }
+    /**
+     * Set options to be used in rcube_imap_generic::connect()
+     */
+    function set_options($opt)
+    {
+        $this->options = array_merge($this->options, (array)$opt);
+    }
 
-  /**
-   * Set a root folder for the IMAP connection.
-   *
-   * Only folders within this root folder will be displayed
-   * and all folder paths will be translated using this folder name
-   *
-   * @param  string   Root folder
-   * @access public
-   */
-  function set_rootdir($root)
+    /**
+     * Set a root folder for the IMAP connection.
+     *
+     * Only folders within this root folder will be displayed
+     * and all folder paths will be translated using this folder name
+     *
+     * @param  string   Root folder
+     * @access public
+     */
+    function set_rootdir($root)
     {
-    if (preg_match('/[.\/]$/', $root)) //(substr($root, -1, 1)==='/')
-      $root = substr($root, 0, -1);
+        if (preg_match('/[.\/]$/', $root)) //(substr($root, -1, 1)==='/')
+            $root = substr($root, 0, -1);
 
-    $this->root_dir = $root;
-    $this->options['rootdir'] = $root;
+        $this->root_dir = $root;
+        $this->options['rootdir'] = $root;
     
-    if (empty($this->delimiter))
-      $this->get_hierarchy_delimiter();
+        if (empty($this->delimiter))
+            $this->get_hierarchy_delimiter();
     }
 
 
-  /**
-   * Set default message charset
-   *
-   * This will be used for message decoding if a charset specification is not available
-   *
-   * @param  string   Charset string
-   * @access public
-   */
-  function set_charset($cs)
+    /**
+     * Set default message charset
+     *
+     * This will be used for message decoding if a charset specification is not available
+     *
+     * @param  string   Charset string
+     * @access public
+     */
+    function set_charset($cs)
     {
-    $this->default_charset = $cs;
+        $this->default_charset = $cs;
     }
 
 
-  /**
-   * This list of folders will be listed above all other folders
-   *
-   * @param  array  Indexed list of folder names
-   * @access public
-   */
-  function set_default_mailboxes($arr)
+    /**
+     * This list of folders will be listed above all other folders
+     *
+     * @param  array  Indexed list of folder names
+     * @access public
+     */
+    function set_default_mailboxes($arr)
     {
-    if (is_array($arr))
-      {
-      $this->default_folders = $arr;
+        if (is_array($arr)) {
+            $this->default_folders = $arr;
 
-      // add inbox if not included
-      if (!in_array('INBOX', $this->default_folders))
-        array_unshift($this->default_folders, 'INBOX');
-      }
+            // add inbox if not included
+            if (!in_array('INBOX', $this->default_folders))
+                array_unshift($this->default_folders, 'INBOX');
+        }
     }
 
 
-  /**
-   * Set internal mailbox reference.
-   *
-   * All operations will be perfomed on this mailbox/folder
-   *
-   * @param  string  Mailbox/Folder name
-   * @access public
-   */
-  function set_mailbox($new_mbox)
+    /**
+     * Set internal mailbox reference.
+     *
+     * All operations will be perfomed on this mailbox/folder
+     *
+     * @param  string  Mailbox/Folder name
+     * @access public
+     */
+    function set_mailbox($new_mbox)
     {
-    $mailbox = $this->mod_mailbox($new_mbox);
+        $mailbox = $this->mod_mailbox($new_mbox);
 
-    if ($this->mailbox == $mailbox)
-      return;
+        if ($this->mailbox == $mailbox)
+            return;
 
-    $this->mailbox = $mailbox;
+        $this->mailbox = $mailbox;
 
-    // clear messagecount cache for this mailbox
-    $this->_clear_messagecount($mailbox);
+        // clear messagecount cache for this mailbox
+        $this->_clear_messagecount($mailbox);
     }
 
 
-  /**
-   * Set internal list page
-   *
-   * @param  number  Page number to list
-   * @access public
-   */
-  function set_page($page)
+    /**
+     * Set internal list page
+     *
+     * @param  number  Page number to list
+     * @access public
+     */
+    function set_page($page)
     {
-    $this->list_page = (int)$page;
+        $this->list_page = (int)$page;
     }
 
 
-  /**
-   * Set internal page size
-   *
-   * @param  number  Number of messages to display on one page
-   * @access public
-   */
-  function set_pagesize($size)
+    /**
+     * Set internal page size
+     *
+     * @param  number  Number of messages to display on one page
+     * @access public
+     */
+    function set_pagesize($size)
     {
-    $this->page_size = (int)$size;
+        $this->page_size = (int)$size;
     }
     
 
-  /**
-   * Save a set of message ids for future message listing methods
-   *
-   * @param  string  IMAP Search query
-   * @param  array   List of message ids or NULL if empty
-   * @param  string  Charset of search string
-   * @param  string  Sorting field
-   */
-  function set_search_set($str=null, $msgs=null, $charset=null, $sort_field=null, $threads=false)
+    /**
+     * Save a set of message ids for future message listing methods
+     *
+     * @param  string  IMAP Search query
+     * @param  array   List of message ids or NULL if empty
+     * @param  string  Charset of search string
+     * @param  string  Sorting field
+     */
+    function set_search_set($str=null, $msgs=null, $charset=null, $sort_field=null, $threads=false)
     {
-    if (is_array($str) && $msgs == null)
-      list($str, $msgs, $charset, $sort_field, $threads) = $str;
-    if ($msgs != null && !is_array($msgs))
-      $msgs = explode(',', $msgs);
+        if (is_array($str) && $msgs == null)
+            list($str, $msgs, $charset, $sort_field, $threads) = $str;
+        if ($msgs != null && !is_array($msgs))
+            $msgs = explode(',', $msgs);
 
-    $this->search_string = $str;
-    $this->search_set = $msgs;
-    $this->search_charset = $charset;
-    $this->search_sort_field = $sort_field;
-    $this->search_threads = $threads;
+        $this->search_string     = $str;
+        $this->search_set        = $msgs;
+        $this->search_charset    = $charset;
+        $this->search_sort_field = $sort_field;
+        $this->search_threads    = $threads;
     }
 
 
-  /**
-   * Return the saved search set as hash array
-   * @return array Search set
-   */
-  function get_search_set()
+    /**
+     * Return the saved search set as hash array
+     * @return array Search set
+     */
+    function get_search_set()
     {
-    return array($this->search_string,
-	$this->search_set,
-	$this->search_charset,
-	$this->search_sort_field,
-	$this->search_threads,
-	);
+        return array($this->search_string,
+	        $this->search_set,
+        	$this->search_charset,
+        	$this->search_sort_field,
+        	$this->search_threads,
+	    );
     }
 
 
-  /**
-   * Returns the currently used mailbox name
-   *
-   * @return  string Name of the mailbox/folder
-   * @access  public
-   */
-  function get_mailbox_name()
+    /**
+     * Returns the currently used mailbox name
+     *
+     * @return  string Name of the mailbox/folder
+     * @access  public
+     */
+    function get_mailbox_name()
     {
-    return $this->conn ? $this->mod_mailbox($this->mailbox, 'out') : '';
+        return $this->conn->connected() ? $this->mod_mailbox($this->mailbox, 'out') : '';
     }
 
 
-  /**
-   * Returns the IMAP server's capability
-   *
-   * @param   string  Capability name
-   * @return  mixed   Capability value or TRUE if supported, FALSE if not
-   * @access  public
-   */
-  function get_capability($cap)
+    /**
+     * Returns the IMAP server's capability
+     *
+     * @param   string  Capability name
+     * @return  mixed   Capability value or TRUE if supported, FALSE if not
+     * @access  public
+     */
+    function get_capability($cap)
     {
-    return iil_C_GetCapability($this->conn, strtoupper($cap));
+        return $this->conn->getCapability(strtoupper($cap));
     }
 
 
-  /**
-   * Sets threading flag to the best supported THREAD algorithm
-   *
-   * @param  boolean  TRUE to enable and FALSE
-   * @return string   Algorithm or false if THREAD is not supported
-   * @access public
-   */
-  function set_threading($enable=false)
+    /**
+     * Sets threading flag to the best supported THREAD algorithm
+     *
+     * @param  boolean  TRUE to enable and FALSE
+     * @return string   Algorithm or false if THREAD is not supported
+     * @access public
+     */
+    function set_threading($enable=false)
     {
-    $this->threading = false;
+        $this->threading = false;
     
-    if ($enable) {
-      if ($this->get_capability('THREAD=REFS'))
-        $this->threading = 'REFS';
-      else if ($this->get_capability('THREAD=REFERENCES'))
-        $this->threading = 'REFERENCES';
-      else if ($this->get_capability('THREAD=ORDEREDSUBJECT'))
-        $this->threading = 'ORDEREDSUBJECT';
-      }
-      
-    return $this->threading;
+        if ($enable) {
+            if ($this->get_capability('THREAD=REFS'))
+                $this->threading = 'REFS';
+            else if ($this->get_capability('THREAD=REFERENCES'))
+                $this->threading = 'REFERENCES';
+            else if ($this->get_capability('THREAD=ORDEREDSUBJECT'))
+                $this->threading = 'ORDEREDSUBJECT';
+        }
+
+        return $this->threading;
     }
 
 
-  /**
-   * Checks the PERMANENTFLAGS capability of the current mailbox
-   * and returns true if the given flag is supported by the IMAP server
-   *
-   * @param   string  Permanentflag name
-   * @return  mixed   True if this flag is supported
-   * @access  public
-   */
-  function check_permflag($flag)
+    /**
+     * Checks the PERMANENTFLAGS capability of the current mailbox
+     * and returns true if the given flag is supported by the IMAP server
+     *
+     * @param   string  Permanentflag name
+     * @return  mixed   True if this flag is supported
+     * @access  public
+     */
+    function check_permflag($flag)
     {
-    $flag = strtoupper($flag);
-    $imap_flag = $GLOBALS['IMAP_FLAGS'][$flag];
-    return (in_array_nocase($imap_flag, $this->conn->permanentflags));
+        $flag = strtoupper($flag);
+        $imap_flag = $this->conn->flags[$flag];
+        return (in_array_nocase($imap_flag, $this->conn->permanentflags));
     }
 
 
-  /**
-   * Returns the delimiter that is used by the IMAP server for folder separation
-   *
-   * @return  string  Delimiter string
-   * @access  public
-   */
-  function get_hierarchy_delimiter()
+    /**
+     * Returns the delimiter that is used by the IMAP server for folder separation
+     *
+     * @return  string  Delimiter string
+     * @access  public
+     */
+    function get_hierarchy_delimiter()
     {
-    if ($this->conn && empty($this->delimiter))
-      $this->delimiter = iil_C_GetHierarchyDelimiter($this->conn);
+        if ($this->conn && empty($this->delimiter))
+            $this->delimiter = $this->conn->getHierarchyDelimiter();
 
-    if (empty($this->delimiter))
-      $this->delimiter = '/';
+        if (empty($this->delimiter))
+            $this->delimiter = '/';
 
-    return $this->delimiter;
+        return $this->delimiter;
     }
 
 
-  /**
-   * Public method for mailbox listing.
-   *
-   * Converts mailbox name with root dir first
-   *
-   * @param   string  Optional root folder
-   * @param   string  Optional filter for mailbox listing
-   * @return  array   List of mailboxes/folders
-   * @access  public
-   */
-  function list_mailboxes($root='', $filter='*')
+    /**
+     * Get message count for a specific mailbox
+     *
+     * @param   string   Mailbox/folder name
+     * @param   string   Mode for count [ALL|THREADS|UNSEEN|RECENT]
+     * @param   boolean  Force reading from server and update cache
+     * @return  int      Number of messages
+     * @access  public
+     */
+    function messagecount($mbox_name='', $mode='ALL', $force=false)
     {
-    $a_out = array();
-    $a_mboxes = $this->_list_mailboxes($root, $filter);
+        $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
+        return $this->_messagecount($mailbox, $mode, $force);
+    }
+
+
+    /**
+     * Private method for getting nr of messages
+     *
+     * @access  private
+     * @see     rcube_imap::messagecount()
+     */
+    private function _messagecount($mailbox='', $mode='ALL', $force=false)
+    {
+        $mode = strtoupper($mode);
+
+        if (empty($mailbox))
+            $mailbox = $this->mailbox;
+
+        // count search set
+        if ($this->search_string && $mailbox == $this->mailbox && ($mode == 'ALL' || $mode == 'THREADS') && !$force) {
+            if ($this->search_threads)
+                return $mode == 'ALL' ? count((array)$this->search_set['depth']) : count((array)$this->search_set['tree']);
+            else
+                return count((array)$this->search_set);
+        }
+    
+        $a_mailbox_cache = $this->get_cache('messagecount');
+    
+        // return cached value
+        if (!$force && is_array($a_mailbox_cache[$mailbox]) && isset($a_mailbox_cache[$mailbox][$mode]))
+            return $a_mailbox_cache[$mailbox][$mode];
+
+        if (!is_array($a_mailbox_cache[$mailbox]))
+            $a_mailbox_cache[$mailbox] = array();
 
-    foreach ($a_mboxes as $mbox_row)
-      {
-      $name = $this->mod_mailbox($mbox_row, 'out');
-      if (strlen($name))
-        $a_out[] = $name;
-      }
+        if ($mode == 'THREADS') {
+            $count = $this->_threadcount($mailbox, $msg_count);
+            $_SESSION['maxuid'][$mailbox] = $msg_count ? $this->_id2uid($msg_count) : 0;
+        }
+        // RECENT count is fetched a bit different
+        else if ($mode == 'RECENT') {
+            $count = $this->conn->checkForRecent($mailbox);
+        }
+        // use SEARCH for message counting
+        else if ($this->skip_deleted) {
+            $search_str = "ALL UNDELETED";
+
+            // get message count and store in cache
+            if ($mode == 'UNSEEN')
+                $search_str .= " UNSEEN";
+
+            // get message count using SEARCH
+            // not very performant but more precise (using UNDELETED)
+            // disable THREADS for this request
+            $threads = $this->threading;
+            $this->threading = false;
+            $index = $this->_search_index($mailbox, $search_str);
+            $this->threading = $threads;
+      
+            $count = is_array($index) ? count($index) : 0;
+
+            if ($mode == 'ALL')
+                $_SESSION['maxuid'][$mailbox] = $index ? $this->_id2uid(max($index)) : 0;
+        }
+        else {
+            if ($mode == 'UNSEEN')
+                $count = $this->conn->countUnseen($mailbox);
+            else {
+                $count = $this->conn->countMessages($mailbox);
+                $_SESSION['maxuid'][$mailbox] = $count ? $this->_id2uid($count) : 0;
+            }
+        }
 
-    // INBOX should always be available
-    if (!in_array('INBOX', $a_out))
-      array_unshift($a_out, 'INBOX');
+        $a_mailbox_cache[$mailbox][$mode] = (int)$count;
 
-    // sort mailboxes
-    $a_out = $this->_sort_mailbox_list($a_out);
+        // write back to cache
+        $this->update_cache('messagecount', $a_mailbox_cache);
 
-    return $a_out;
+        return (int)$count;
     }
 
 
-  /**
-   * Private method for mailbox listing
-   *
-   * @return  array   List of mailboxes/folders
-   * @see     rcube_imap::list_mailboxes()
-   * @access  private
-   */
-  private function _list_mailboxes($root='', $filter='*')
+    /**
+     * Private method for getting nr of threads
+     *
+     * @access  private
+     * @see     rcube_imap::messagecount()
+     */
+    private function _threadcount($mailbox, &$msg_count)
     {
-    $a_defaults = $a_out = array();
+        if (!empty($this->icache['threads']))
+            return count($this->icache['threads']['tree']);
     
-    // get cached folder list    
-    $a_mboxes = $this->get_cache('mailboxes');
-    if (is_array($a_mboxes))
-      return $a_mboxes;
-
-    // Give plugins a chance to provide a list of mailboxes
-    $data = rcmail::get_instance()->plugins->exec_hook('list_mailboxes',array('root'=>$root,'filter'=>$filter));
-    if (isset($data['folders'])) {
-        $a_folders = $data['folders'];
-    }
-    else {
-        // retrieve list of folders from IMAP server
-        $a_folders = iil_C_ListSubscribed($this->conn, $this->mod_mailbox($root), $filter);
-    }
+        list ($thread_tree, $msg_depth, $has_children) = $this->_fetch_threads($mailbox);
     
-    if (!is_array($a_folders) || !sizeof($a_folders))
-      $a_folders = array();
+        $msg_count = count($msg_depth);
 
-    // write mailboxlist to cache
-    $this->update_cache('mailboxes', $a_folders);
-    
-    return $a_folders;
-    }
+//    $this->update_thread_cache($mailbox, $thread_tree, $msg_depth, $has_children);
+        return count($thread_tree);  
+    }
+
+
+    /**
+     * Public method for listing headers
+     * convert mailbox name with root dir first
+     *
+     * @param   string   Mailbox/folder name
+     * @param   int      Current page to list
+     * @param   string   Header field to sort by
+     * @param   string   Sort order [ASC|DESC]
+     * @param   boolean  Number of slice items to extract from result array
+     * @return  array    Indexed array with message header objects
+     * @access  public   
+     */
+    function list_headers($mbox_name='', $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
+    {
+        $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
+        return $this->_list_headers($mailbox, $page, $sort_field, $sort_order, false, $slice);
+    }
+
+
+    /**
+     * Private method for listing message headers
+     *
+     * @access  private
+     * @see     rcube_imap::list_headers
+     */
+    private function _list_headers($mailbox='', $page=NULL, $sort_field=NULL, $sort_order=NULL, $recursive=false, $slice=0)
+    {
+        if (!strlen($mailbox))
+            return array();
+
+        // use saved message set
+        if ($this->search_string && $mailbox == $this->mailbox)
+            return $this->_list_header_set($mailbox, $page, $sort_field, $sort_order, $slice);
+
+        if ($this->threading)
+            return $this->_list_thread_headers($mailbox, $page, $sort_field, $sort_order, $recursive, $slice);
+
+        $this->_set_sort_order($sort_field, $sort_order);
+
+        $page         = $page ? $page : $this->list_page;
+        $cache_key    = $mailbox.'.msg';
+        $cache_status = $this->check_cache_status($mailbox, $cache_key);
+
+        // cache is OK, we can get all messages from local cache
+        if ($cache_status>0) {
+            $start_msg = ($page-1) * $this->page_size;
+            $a_msg_headers = $this->get_message_cache($cache_key, $start_msg,
+                $start_msg+$this->page_size, $this->sort_field, $this->sort_order);
+            $result = array_values($a_msg_headers);
+            if ($slice)
+                $result = array_slice($result, -$slice, $slice);
+            return $result;
+        }
+        // cache is dirty, sync it
+        else if ($this->caching_enabled && $cache_status==-1 && !$recursive) {
+            $this->sync_header_index($mailbox);
+            return $this->_list_headers($mailbox, $page, $this->sort_field, $this->sort_order, true, $slice);
+        }
 
+        // retrieve headers from IMAP
+        $a_msg_headers = array();
+
+        // use message index sort as default sorting (for better performance)
+        if (!$this->sort_field) {
+            if ($this->skip_deleted) {
+                // @TODO: this could be cached
+                if ($msg_index = $this->_search_index($mailbox, 'ALL UNDELETED')) {
+                    $max = max($msg_index);
+                    list($begin, $end) = $this->_get_message_range(count($msg_index), $page);
+                    $msg_index = array_slice($msg_index, $begin, $end-$begin);
+                }
+            }
+            else if ($max = $this->conn->countMessages($mailbox)) {
+                list($begin, $end) = $this->_get_message_range($max, $page);
+                $msg_index = range($begin+1, $end);
+            }
+            else
+                $msg_index = array();
 
-  /**
-   * Get message count for a specific mailbox
-   *
-   * @param   string   Mailbox/folder name
-   * @param   string   Mode for count [ALL|THREADS|UNSEEN|RECENT]
-   * @param   boolean  Force reading from server and update cache
-   * @return  int      Number of messages
-   * @access  public
-   */
-  function messagecount($mbox_name='', $mode='ALL', $force=false)
-    {
-    $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
-    return $this->_messagecount($mailbox, $mode, $force);
-    }
+            if ($slice)
+                $msg_index = array_slice($msg_index, ($this->sort_order == 'DESC' ? 0 : -$slice), $slice);
 
+            // fetch reqested headers from server
+            if ($msg_index)
+                $this->_fetch_headers($mailbox, join(",", $msg_index), $a_msg_headers, $cache_key);
+        }
+        // use SORT command
+        else if ($this->get_capability('SORT')) {
+            if ($msg_index = $this->conn->sort($mailbox, $this->sort_field, $this->skip_deleted ? 'UNDELETED' : '')) {
+                list($begin, $end) = $this->_get_message_range(count($msg_index), $page);
+                $max = max($msg_index);
+                $msg_index = array_slice($msg_index, $begin, $end-$begin);
+
+                if ($slice)
+                    $msg_index = array_slice($msg_index, ($this->sort_order == 'DESC' ? 0 : -$slice), $slice);
+
+                // fetch reqested headers from server
+                $this->_fetch_headers($mailbox, join(',', $msg_index), $a_msg_headers, $cache_key);
+            }
+        }
+        // fetch specified header for all messages and sort
+        else if ($a_index = $this->conn->fetchHeaderIndex($mailbox, "1:*", $this->sort_field, $this->skip_deleted)) {
+            asort($a_index); // ASC
+            $msg_index = array_keys($a_index);
+            $max = max($msg_index);
+            list($begin, $end) = $this->_get_message_range(count($msg_index), $page);
+            $msg_index = array_slice($msg_index, $begin, $end-$begin);
 
-  /**
-   * Private method for getting nr of messages
-   *
-   * @access  private
-   * @see     rcube_imap::messagecount()
-   */
-  private function _messagecount($mailbox='', $mode='ALL', $force=false)
-    {
-    $mode = strtoupper($mode);
+            if ($slice)
+                $msg_index = array_slice($msg_index, ($this->sort_order == 'DESC' ? 0 : -$slice), $slice);
 
-    if (empty($mailbox))
-      $mailbox = $this->mailbox;
+            // fetch reqested headers from server
+            $this->_fetch_headers($mailbox, join(",", $msg_index), $a_msg_headers, $cache_key);
+        }
 
-    // count search set
-    if ($this->search_string && $mailbox == $this->mailbox && ($mode == 'ALL' || $mode == 'THREADS') && !$force) {
-      if ($this->search_threads)
-        return $mode == 'ALL' ? count((array)$this->search_set['depth']) : count((array)$this->search_set['tree']);
-      else
-        return count((array)$this->search_set);
-      }
-    
-    $a_mailbox_cache = $this->get_cache('messagecount');
+        // delete cached messages with a higher index than $max+1
+        // Changed $max to $max+1 to fix this bug : #1484295
+        $this->clear_message_cache($cache_key, $max + 1);
+
+        // kick child process to sync cache
+        // ...
+
+        // return empty array if no messages found
+        if (!is_array($a_msg_headers) || empty($a_msg_headers))
+            return array();
     
-    // return cached value
-    if (!$force && is_array($a_mailbox_cache[$mailbox]) && isset($a_mailbox_cache[$mailbox][$mode]))
-      return $a_mailbox_cache[$mailbox][$mode];
+        // use this class for message sorting
+        $sorter = new rcube_header_sorter();
+        $sorter->set_sequence_numbers($msg_index);
+        $sorter->sort_headers($a_msg_headers);
 
-    if (!is_array($a_mailbox_cache[$mailbox]))
-      $a_mailbox_cache[$mailbox] = array();
+        if ($this->sort_order == 'DESC')
+            $a_msg_headers = array_reverse($a_msg_headers);	    
 
-    if ($mode == 'THREADS') {
-      $count = $this->_threadcount($mailbox, $msg_count);
-      $_SESSION['maxuid'][$mailbox] = $msg_count ? $this->_id2uid($msg_count) : 0;
-      }
-    // RECENT count is fetched a bit different
-    else if ($mode == 'RECENT') {
-       $count = iil_C_CheckForRecent($this->conn, $mailbox);
-      }
-    // use SEARCH for message counting
-    else if ($this->skip_deleted) {
-      $search_str = "ALL UNDELETED";
+        return array_values($a_msg_headers);
+    }
 
-      // get message count and store in cache
-      if ($mode == 'UNSEEN')
-        $search_str .= " UNSEEN";
 
-      // get message count using SEARCH
-      // not very performant but more precise (using UNDELETED)
-      // disable THREADS for this request
-      $threads = $this->threading;
-      $this->threading = false;
-      $index = $this->_search_index($mailbox, $search_str);
-      $this->threading = $threads;
-      
-      $count = is_array($index) ? count($index) : 0;
+    /**
+     * Private method for listing message headers using threads
+     *
+     * @access  private
+     * @see     rcube_imap::list_headers
+     */
+    private function _list_thread_headers($mailbox, $page=NULL, $sort_field=NULL, $sort_order=NULL, $recursive=false, $slice=0)
+    {
+        $this->_set_sort_order($sort_field, $sort_order);
 
-      if ($mode == 'ALL')
-        $_SESSION['maxuid'][$mailbox] = $index ? $this->_id2uid(max($index)) : 0;
-      }
-    else {
-      if ($mode == 'UNSEEN')
-        $count = iil_C_CountUnseen($this->conn, $mailbox);
-      else {
-        $count = iil_C_CountMessages($this->conn, $mailbox);
-        $_SESSION['maxuid'][$mailbox] = $count ? $this->_id2uid($count) : 0;
-      }
-    }
+        $page = $page ? $page : $this->list_page;
+//    $cache_key = $mailbox.'.msg';
+//    $cache_status = $this->check_cache_status($mailbox, $cache_key);
+
+        // get all threads (default sort order)
+        list ($thread_tree, $msg_depth, $has_children) = $this->_fetch_threads($mailbox);
 
-    $a_mailbox_cache[$mailbox][$mode] = (int)$count;
+        if (empty($thread_tree))
+            return array();
 
-    // write back to cache
-    $this->update_cache('messagecount', $a_mailbox_cache);
+        $msg_index = $this->_sort_threads($mailbox, $thread_tree);
 
-    return (int)$count;
+        return $this->_fetch_thread_headers($mailbox,
+            $thread_tree, $msg_depth, $has_children, $msg_index, $page, $slice);
     }
 
 
-  /**
-   * Private method for getting nr of threads
-   *
-   * @access  private
-   * @see     rcube_imap::messagecount()
-   */
-  private function _threadcount($mailbox, &$msg_count)
+    /**
+     * Private method for fetching threads data
+     *
+     * @param   string   Mailbox/folder name
+     * @return  array    Array with thread data
+     * @access  private
+     */
+    private function _fetch_threads($mailbox)
     {
-    if (!empty($this->icache['threads']))
-      return count($this->icache['threads']['tree']);
-    
-    list ($thread_tree, $msg_depth, $has_children) = $this->_fetch_threads($mailbox);
-    
-    $msg_count = count($msg_depth);
-
-//    $this->update_thread_cache($mailbox, $thread_tree, $msg_depth, $has_children);
-    return count($thread_tree);  
-    }
-
-
-  /**
-   * Public method for listing headers
-   * convert mailbox name with root dir first
-   *
-   * @param   string   Mailbox/folder name
-   * @param   int      Current page to list
-   * @param   string   Header field to sort by
-   * @param   string   Sort order [ASC|DESC]
-   * @param   boolean  Number of slice items to extract from result array
-   * @return  array    Indexed array with message header objects
-   * @access  public   
-   */
-  function list_headers($mbox_name='', $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
-    {
-    $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
-    return $this->_list_headers($mailbox, $page, $sort_field, $sort_order, false, $slice);
-    }
-
-
-  /**
-   * Private method for listing message headers
-   *
-   * @access  private
-   * @see     rcube_imap::list_headers
-   */
-  private function _list_headers($mailbox='', $page=NULL, $sort_field=NULL, $sort_order=NULL, $recursive=false, $slice=0)
-    {
-    if (!strlen($mailbox))
-      return array();
-
-    // use saved message set
-    if ($this->search_string && $mailbox == $this->mailbox)
-      return $this->_list_header_set($mailbox, $page, $sort_field, $sort_order, $slice);
-
-    if ($this->threading)
-      return $this->_list_thread_headers($mailbox, $page, $sort_field, $sort_order, $recursive, $slice);
-
-    $this->_set_sort_order($sort_field, $sort_order);
-
-    $page = $page ? $page : $this->list_page;
-    $cache_key = $mailbox.'.msg';
-    $cache_status = $this->check_cache_status($mailbox, $cache_key);
-
-    // cache is OK, we can get all messages from local cache
-    if ($cache_status>0)
-      {
-      $start_msg = ($page-1) * $this->page_size;
-      $a_msg_headers = $this->get_message_cache($cache_key, $start_msg, $start_msg+$this->page_size, $this->sort_field, $this->sort_order);
-      $result = array_values($a_msg_headers);
-      if ($slice)
-        $result = array_slice($result, -$slice, $slice);
-      return $result;
-      }
-    // cache is dirty, sync it
-    else if ($this->caching_enabled && $cache_status==-1 && !$recursive)
-      {
-      $this->sync_header_index($mailbox);
-      return $this->_list_headers($mailbox, $page, $this->sort_field, $this->sort_order, true, $slice);
-      }
-
-    // retrieve headers from IMAP
-    $a_msg_headers = array();
-
-    // use message index sort as default sorting (for better performance)
-    if (!$this->sort_field)
-      {
-        if ($this->skip_deleted) {
-          // @TODO: this could be cached
-          if ($msg_index = $this->_search_index($mailbox, 'ALL UNDELETED')) {
-            $max = max($msg_index);
-            list($begin, $end) = $this->_get_message_range(count($msg_index), $page);
-            $msg_index = array_slice($msg_index, $begin, $end-$begin);
-          }
-        }
-        else if ($max = iil_C_CountMessages($this->conn, $mailbox)) {
-          list($begin, $end) = $this->_get_message_range($max, $page);
-          $msg_index = range($begin+1, $end);
+        if (empty($this->icache['threads'])) {
+            // get all threads
+            list ($thread_tree, $msg_depth, $has_children) = $this->conn->thread(
+                $mailbox, $this->threading, $this->skip_deleted ? 'UNDELETED' : '');
+   
+            // add to internal (fast) cache
+            $this->icache['threads'] = array();
+            $this->icache['threads']['tree'] = $thread_tree;
+            $this->icache['threads']['depth'] = $msg_depth;
+            $this->icache['threads']['has_children'] = $has_children;
         }
-        else
-          $msg_index = array();
 
-        if ($slice)
-          $msg_index = array_slice($msg_index, ($this->sort_order == 'DESC' ? 0 : -$slice), $slice);
+        return array(
+            $this->icache['threads']['tree'],
+            $this->icache['threads']['depth'],
+            $this->icache['threads']['has_children'],
+        );
+    }
 
-        // fetch reqested headers from server
-        if ($msg_index)
-          $this->_fetch_headers($mailbox, join(",", $msg_index), $a_msg_headers, $cache_key);
-      }
-    // use SORT command
-    else if ($this->get_capability('SORT'))
-      {
-      if ($msg_index = iil_C_Sort($this->conn, $mailbox, $this->sort_field, $this->skip_deleted ? 'UNDELETED' : '')) {
+
+    /**
+     * Private method for fetching threaded messages headers
+     *
+     * @access  private
+     */
+    private function _fetch_thread_headers($mailbox, $thread_tree, $msg_depth, $has_children, $msg_index, $page, $slice=0)
+    {
+        $cache_key = $mailbox.'.msg';
+        // now get IDs for current page
         list($begin, $end) = $this->_get_message_range(count($msg_index), $page);
-        $max = max($msg_index);
         $msg_index = array_slice($msg_index, $begin, $end-$begin);
 
         if ($slice)
-          $msg_index = array_slice($msg_index, ($this->sort_order == 'DESC' ? 0 : -$slice), $slice);
+            $msg_index = array_slice($msg_index, ($this->sort_order == 'DESC' ? 0 : -$slice), $slice);
 
-        // fetch reqested headers from server
-        $this->_fetch_headers($mailbox, join(',', $msg_index), $a_msg_headers, $cache_key);
+        if ($this->sort_order == 'DESC')
+            $msg_index = array_reverse($msg_index);
+
+        // flatten threads array
+        // @TODO: fetch children only in expanded mode (?)
+        $all_ids = array();
+        foreach($msg_index as $root) {
+            $all_ids[] = $root;
+            if (!empty($thread_tree[$root]))
+                $all_ids = array_merge($all_ids, array_keys_recursive($thread_tree[$root]));
         }
-      }
-    // fetch specified header for all messages and sort
-    else if ($a_index = iil_C_FetchHeaderIndex($this->conn, $mailbox, "1:*", $this->sort_field, $this->skip_deleted))
-      {
-      asort($a_index); // ASC
-      $msg_index = array_keys($a_index);
-      $max = max($msg_index);
-      list($begin, $end) = $this->_get_message_range(count($msg_index), $page);
-      $msg_index = array_slice($msg_index, $begin, $end-$begin);
 
-      if ($slice)
-        $msg_index = array_slice($msg_index, ($this->sort_order == 'DESC' ? 0 : -$slice), $slice);
+        // fetch reqested headers from server
+        $this->_fetch_headers($mailbox, $all_ids, $a_msg_headers, $cache_key);
+
+        // return empty array if no messages found
+        if (!is_array($a_msg_headers) || empty($a_msg_headers))
+            return array();
+    
+        // use this class for message sorting
+        $sorter = new rcube_header_sorter();
+        $sorter->set_sequence_numbers($all_ids);
+        $sorter->sort_headers($a_msg_headers);
+
+        // Set depth, has_children and unread_children fields in headers
+        $this->_set_thread_flags($a_msg_headers, $msg_depth, $has_children);
 
-      // fetch reqested headers from server
-      $this->_fetch_headers($mailbox, join(",", $msg_index), $a_msg_headers, $cache_key);
-      }
+        return array_values($a_msg_headers);
+    }
 
-    // delete cached messages with a higher index than $max+1
-    // Changed $max to $max+1 to fix this bug : #1484295
-    $this->clear_message_cache($cache_key, $max + 1);
 
-    // kick child process to sync cache
-    // ...
+    /**
+     * Private method for setting threaded messages flags:
+     * depth, has_children and unread_children
+     *
+     * @param  array   Reference to headers array indexed by message ID
+     * @param  array   Array of messages depth indexed by message ID
+     * @param  array   Array of messages children flags indexed by message ID
+     * @return array   Message headers array indexed by message ID
+     * @access private
+     */
+    private function _set_thread_flags(&$headers, $msg_depth, $msg_children)
+    {
+        $parents = array();
 
-    // return empty array if no messages found
-    if (!is_array($a_msg_headers) || empty($a_msg_headers))
-      return array();
-    
-    // use this class for message sorting
-    $sorter = new rcube_header_sorter();
-    $sorter->set_sequence_numbers($msg_index);
-    $sorter->sort_headers($a_msg_headers);
+        foreach ($headers as $idx => $header) {
+            $id = $header->id;
+            $depth = $msg_depth[$id];
+            $parents = array_slice($parents, 0, $depth);
 
-    if ($this->sort_order == 'DESC')
-      $a_msg_headers = array_reverse($a_msg_headers);	    
+            if (!empty($parents)) {
+                $headers[$idx]->parent_uid = end($parents);
+                if (!$header->seen)
+                    $headers[$parents[0]]->unread_children++;
+            }
+            array_push($parents, $header->uid);
 
-    return array_values($a_msg_headers);
+            $headers[$idx]->depth = $depth;
+            $headers[$idx]->has_children = $msg_children[$id];
+        }
     }
 
 
-  /**
-   * Private method for listing message headers using threads
-   *
-   * @access  private
-   * @see     rcube_imap::list_headers
-   */
-  private function _list_thread_headers($mailbox, $page=NULL, $sort_field=NULL, $sort_order=NULL, $recursive=false, $slice=0)
+    /**
+     * Private method for listing a set of message headers (search results)
+     *
+     * @param   string   Mailbox/folder name
+     * @param   int      Current page to list
+     * @param   string   Header field to sort by
+     * @param   string   Sort order [ASC|DESC]
+     * @param   boolean  Number of slice items to extract from result array
+     * @return  array    Indexed array with message header objects
+     * @access  private
+     * @see     rcube_imap::list_header_set()
+     */
+    private function _list_header_set($mailbox, $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
     {
-    $this->_set_sort_order($sort_field, $sort_order);
+        if (!strlen($mailbox) || empty($this->search_set))
+            return array();
 
-    $page = $page ? $page : $this->list_page;
-//    $cache_key = $mailbox.'.msg';
-//    $cache_status = $this->check_cache_status($mailbox, $cache_key);
+        // use saved messages from searching
+        if ($this->threading)
+            return $this->_list_thread_header_set($mailbox, $page, $sort_field, $sort_order, $slice);
 
-    // get all threads (default sort order)
-    list ($thread_tree, $msg_depth, $has_children) = $this->_fetch_threads($mailbox);
+        // search set is threaded, we need a new one
+        if ($this->search_threads)
+            $this->search('', $this->search_string, $this->search_charset, $sort_field);
+    
+        $msgs = $this->search_set;
+        $a_msg_headers = array();
+        $page = $page ? $page : $this->list_page;
+        $start_msg = ($page-1) * $this->page_size;
 
-    if (empty($thread_tree))
-      return array();
+        $this->_set_sort_order($sort_field, $sort_order);
 
-    $msg_index = $this->_sort_threads($mailbox, $thread_tree);
+        // quickest method (default sorting)
+        if (!$this->search_sort_field && !$this->sort_field) {
+            if ($sort_order == 'DESC')
+                $msgs = array_reverse($msgs);
 
-    return $this->_fetch_thread_headers($mailbox, $thread_tree, $msg_depth, $has_children,
-      $msg_index, $page, $slice);
-    }
+            // get messages uids for one page
+            $msgs = array_slice(array_values($msgs), $start_msg, min(count($msgs)-$start_msg, $this->page_size));
 
+            if ($slice)
+                $msgs = array_slice($msgs, -$slice, $slice);
 
-  /**
-   * Private method for fetching threads data
-   *
-   * @param   string   Mailbox/folder name
-   * @return  array    Array with thread data
-   * @access  private
-   */
-  private function _fetch_threads($mailbox)
-    {
-    if (empty($this->icache['threads'])) {
-      // get all threads
-      list ($thread_tree, $msg_depth, $has_children) = iil_C_Thread($this->conn,
-        $mailbox, $this->threading, $this->skip_deleted ? 'UNDELETED' : '');
-   
-      // add to internal (fast) cache
-      $this->icache['threads'] = array();
-      $this->icache['threads']['tree'] = $thread_tree;
-      $this->icache['threads']['depth'] = $msg_depth;
-      $this->icache['threads']['has_children'] = $has_children;
-      }
-
-    return array(
-      $this->icache['threads']['tree'],
-      $this->icache['threads']['depth'],
-      $this->icache['threads']['has_children'],
-      );
-    }
-
-
-  /**
-   * Private method for fetching threaded messages headers
-   *
-   * @access  private
-   */
-  private function _fetch_thread_headers($mailbox, $thread_tree, $msg_depth, $has_children, $msg_index, $page, $slice=0)
-    {
-    $cache_key = $mailbox.'.msg';
-    // now get IDs for current page
-    list($begin, $end) = $this->_get_message_range(count($msg_index), $page);
-    $msg_index = array_slice($msg_index, $begin, $end-$begin);
-
-    if ($slice)
-      $msg_index = array_slice($msg_index, ($this->sort_order == 'DESC' ? 0 : -$slice), $slice);
-
-    if ($this->sort_order == 'DESC')
-      $msg_index = array_reverse($msg_index);
-
-    // flatten threads array
-    // @TODO: fetch children only in expanded mode
-    $all_ids = array();
-    foreach($msg_index as $root) {
-      $all_ids[] = $root;
-      if (!empty($thread_tree[$root]))
-        $all_ids = array_merge($all_ids, array_keys_recursive($thread_tree[$root]));
-      }
-
-    // fetch reqested headers from server
-    $this->_fetch_headers($mailbox, $all_ids, $a_msg_headers, $cache_key);
-
-    // return empty array if no messages found
-    if (!is_array($a_msg_headers) || empty($a_msg_headers))
-      return array();
-    
-    // use this class for message sorting
-    $sorter = new rcube_header_sorter();
-    $sorter->set_sequence_numbers($all_ids);
-    $sorter->sort_headers($a_msg_headers);
-
-    // Set depth, has_children and unread_children fields in headers
-    $this->_set_thread_flags($a_msg_headers, $msg_depth, $has_children);
-
-    return array_values($a_msg_headers);
-    }
-
-
-  /**
-   * Private method for setting threaded messages flags:
-   * depth, has_children and unread_children
-   *
-   * @param  array   Reference to headers array indexed by message ID
-   * @param  array   Array of messages depth indexed by message ID
-   * @param  array   Array of messages children flags indexed by message ID
-   * @return array   Message headers array indexed by message ID
-   * @access private
-   */
-  private function _set_thread_flags(&$headers, $msg_depth, $msg_children)
-    {
-    $parents = array();
-
-    foreach ($headers as $idx => $header) {
-      $id = $header->id;
-      $depth = $msg_depth[$id];
-      $parents = array_slice($parents, 0, $depth);
-
-      if (!empty($parents)) {
-        $headers[$idx]->parent_uid = end($parents);
-        if (!$header->seen)
-          $headers[$parents[0]]->unread_children++;
-        }
-      array_push($parents, $header->uid);
-
-      $headers[$idx]->depth = $depth;
-      $headers[$idx]->has_children = $msg_children[$id];
-      }
-    }
-
-
-  /**
-   * Private method for listing a set of message headers (search results)
-   *
-   * @param   string   Mailbox/folder name
-   * @param   int      Current page to list
-   * @param   string   Header field to sort by
-   * @param   string   Sort order [ASC|DESC]
-   * @param   boolean  Number of slice items to extract from result array
-   * @return  array    Indexed array with message header objects
-   * @access  private
-   * @see     rcube_imap::list_header_set()
-   */
-  private function _list_header_set($mailbox, $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
-    {
-    if (!strlen($mailbox) || empty($this->search_set))
-      return array();
-
-    // use saved messages from searching
-    if ($this->threading)
-      return $this->_list_thread_header_set($mailbox, $page, $sort_field, $sort_order, $slice);
-
-    // search set is threaded, we need a new one
-    if ($this->search_threads)
-      $this->search('', $this->search_string, $this->search_charset, $sort_field);
-    
-    $msgs = $this->search_set;
-    $a_msg_headers = array();
-    $page = $page ? $page : $this->list_page;
-    $start_msg = ($page-1) * $this->page_size;
-
-    $this->_set_sort_order($sort_field, $sort_order);
-
-    // quickest method (default sorting)
-    if (!$this->search_sort_field && !$this->sort_field)
-      {
-      if ($sort_order == 'DESC')
-        $msgs = array_reverse($msgs);
-
-      // get messages uids for one page
-      $msgs = array_slice(array_values($msgs), $start_msg, min(count($msgs)-$start_msg, $this->page_size));
-
-      if ($slice)
-        $msgs = array_slice($msgs, -$slice, $slice);
-
-      // fetch headers
-      $this->_fetch_headers($mailbox, join(',',$msgs), $a_msg_headers, NULL);
+            // fetch headers
+            $this->_fetch_headers($mailbox, join(',',$msgs), $a_msg_headers, NULL);
 
-      // I didn't found in RFC that FETCH always returns messages sorted by index
-      $sorter = new rcube_header_sorter();
-      $sorter->set_sequence_numbers($msgs);
-      $sorter->sort_headers($a_msg_headers);
+            // I didn't found in RFC that FETCH always returns messages sorted by index
+            $sorter = new rcube_header_sorter();
+            $sorter->set_sequence_numbers($msgs);
+            $sorter->sort_headers($a_msg_headers);
 
-      return array_values($a_msg_headers);
-      }
+            return array_values($a_msg_headers);
+        }
 
-    // sorted messages, so we can first slice array and then fetch only wanted headers
-    if ($this->get_capability('SORT')) // SORT searching result
-      {
-      // reset search set if sorting field has been changed
-      if ($this->sort_field && $this->search_sort_field != $this->sort_field)
-        $msgs = $this->search('', $this->search_string, $this->search_charset, $this->sort_field);
+        // sorted messages, so we can first slice array and then fetch only wanted headers
+        if ($this->get_capability('SORT')) { // SORT searching result
+            // reset search set if sorting field has been changed
+            if ($this->sort_field && $this->search_sort_field != $this->sort_field)
+                $msgs = $this->search('', $this->search_string, $this->search_charset, $this->sort_field);
 
-      // return empty array if no messages found
-      if (empty($msgs))
-        return array();
+            // return empty array if no messages found
+            if (empty($msgs))
+                return array();
 
-      if ($sort_order == 'DESC')
-        $msgs = array_reverse($msgs);
+            if ($sort_order == 'DESC')
+                $msgs = array_reverse($msgs);
 
-      // get messages uids for one page
-      $msgs = array_slice(array_values($msgs), $start_msg, min(count($msgs)-$start_msg, $this->page_size));
+            // get messages uids for one page
+            $msgs = array_slice(array_values($msgs), $start_msg, min(count($msgs)-$start_msg, $this->page_size));
 
-      if ($slice)
-        $msgs = array_slice($msgs, -$slice, $slice);
+            if ($slice)
+                $msgs = array_slice($msgs, -$slice, $slice);
 
-      // fetch headers
-      $this->_fetch_headers($mailbox, join(',',$msgs), $a_msg_headers, NULL);
+            // fetch headers
+            $this->_fetch_headers($mailbox, join(',',$msgs), $a_msg_headers, NULL);
 
-      $sorter = new rcube_header_sorter();
-      $sorter->set_sequence_numbers($msgs);
-      $sorter->sort_headers($a_msg_headers);
+            $sorter = new rcube_header_sorter();
+            $sorter->set_sequence_numbers($msgs);
+            $sorter->sort_headers($a_msg_headers);
 
-      return array_values($a_msg_headers);
-      }
-    else { // SEARCH result, need sorting
-      $cnt = count($msgs);
-      // 300: experimantal value for best result
-      if (($cnt > 300 && $cnt > $this->page_size) || !$this->sort_field) {
-        // use memory less expensive (and quick) method for big result set
-        $a_index = $this->message_index('', $this->sort_field, $this->sort_order);
-        // get messages uids for one page...
-        $msgs = array_slice($a_index, $start_msg, min($cnt-$start_msg, $this->page_size));
-        if ($slice)
-          $msgs = array_slice($msgs, -$slice, $slice);
-        // ...and fetch headers
-        $this->_fetch_headers($mailbox, join(',', $msgs), $a_msg_headers, NULL);
+            return array_values($a_msg_headers);
+        }
+        else { // SEARCH result, need sorting
+            $cnt = count($msgs);
+            // 300: experimantal value for best result
+            if (($cnt > 300 && $cnt > $this->page_size) || !$this->sort_field) {
+                // use memory less expensive (and quick) method for big result set
+                $a_index = $this->message_index('', $this->sort_field, $this->sort_order);
+                // get messages uids for one page...
+                $msgs = array_slice($a_index, $start_msg, min($cnt-$start_msg, $this->page_size));
+                if ($slice)
+                    $msgs = array_slice($msgs, -$slice, $slice);
+                // ...and fetch headers
+                $this->_fetch_headers($mailbox, join(',', $msgs), $a_msg_headers, NULL);
+
+                // return empty array if no messages found
+                if (!is_array($a_msg_headers) || empty($a_msg_headers))
+                    return array();
+
+                $sorter = new rcube_header_sorter();
+                $sorter->set_sequence_numbers($msgs);
+                $sorter->sort_headers($a_msg_headers);
+
+                return array_values($a_msg_headers);
+            }
+            else {
+                // for small result set we can fetch all messages headers
+                $this->_fetch_headers($mailbox, join(',', $msgs), $a_msg_headers, NULL);
+    
+                // return empty array if no messages found
+                if (!is_array($a_msg_headers) || empty($a_msg_headers))
+                    return array();
 
-        // return empty array if no messages found
-        if (!is_array($a_msg_headers) || empty($a_msg_headers))
-          return array();
+                // if not already sorted
+                $a_msg_headers = $this->conn->sortHeaders(
+                    $a_msg_headers, $this->sort_field, $this->sort_order);
 
-        $sorter = new rcube_header_sorter();
-        $sorter->set_sequence_numbers($msgs);
-        $sorter->sort_headers($a_msg_headers);
+                // only return the requested part of the set
+                $a_msg_headers = array_slice(array_values($a_msg_headers),
+                    $start_msg, min($cnt-$start_msg, $this->page_size));
 
-        return array_values($a_msg_headers);
-      }
-      else {
-        // for small result set we can fetch all messages headers
-        $this->_fetch_headers($mailbox, join(',', $msgs), $a_msg_headers, NULL);
-    
-        // return empty array if no messages found
-        if (!is_array($a_msg_headers) || empty($a_msg_headers))
-          return array();
+                if ($slice)
+                    $a_msg_headers = array_slice($a_msg_headers, -$slice, $slice);
 
-        // if not already sorted
-        $a_msg_headers = iil_SortHeaders($a_msg_headers, $this->sort_field, $this->sort_order);
+                return $a_msg_headers;
+            }
+        }
+    }
 
-        // only return the requested part of the set
-        $a_msg_headers = array_slice(array_values($a_msg_headers), $start_msg, min($cnt-$start_msg, $this->page_size));
-        if ($slice)
-          $a_msg_headers = array_slice($a_msg_headers, -$slice, $slice);
 
-        return $a_msg_headers;
-        }
-      }
-    }
-
-
-  /**
-   * Private method for listing a set of threaded message headers (search results)
-   *
-   * @param   string   Mailbox/folder name
-   * @param   int      Current page to list
-   * @param   string   Header field to sort by
-   * @param   string   Sort order [ASC|DESC]
-   * @param   boolean  Number of slice items to extract from result array
-   * @return  array    Indexed array with message header objects
-   * @access  private
-   * @see     rcube_imap::list_header_set()
-   */
-  private function _list_thread_header_set($mailbox, $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
-    {
-    // update search_set if previous data was fetched with disabled threading
-    if (!$this->search_threads)
-      $this->search('', $this->search_string, $this->search_charset, $sort_field);
-
-    $thread_tree = $this->search_set['tree'];
-    $msg_depth = $this->search_set['depth'];
-    $has_children = $this->search_set['children'];
-    $a_msg_headers = array();
-
-    $page = $page ? $page : $this->list_page;
-    $start_msg = ($page-1) * $this->page_size;
-
-    $this->_set_sort_order($sort_field, $sort_order);
-
-    $msg_index = $this->_sort_threads($mailbox, $thread_tree, array_keys($msg_depth));
-
-    return $this->_fetch_thread_headers($mailbox, $thread_tree, $msg_depth, $has_children, $msg_index, $page, $slice=0);
-    }
-
-
-  /**
-   * Helper function to get first and last index of the requested set
-   *
-   * @param  int     message count
-   * @param  mixed   page number to show, or string 'all'
-   * @return array   array with two values: first index, last index
-   * @access private
-   */
-  private function _get_message_range($max, $page)
-    {
-    $start_msg = ($page-1) * $this->page_size;
-    
-    if ($page=='all')
-      {
-      $begin = 0;
-      $end = $max;
-      }
-    else if ($this->sort_order=='DESC')
-      {
-      $begin = $max - $this->page_size - $start_msg;
-      $end =   $max - $start_msg;
-      }
-    else
-      {
-      $begin = $start_msg;
-      $end   = $start_msg + $this->page_size;
-      }
-
-    if ($begin < 0) $begin = 0;
-    if ($end < 0) $end = $max;
-    if ($end > $max) $end = $max;
-    
-    return array($begin, $end);
-    }
-    
-
-  /**
-   * Fetches message headers
-   * Used for loop
-   *
-   * @param  string  Mailbox name
-   * @param  string  Message index to fetch
-   * @param  array   Reference to message headers array
-   * @param  array   Array with cache index
-   * @return int     Messages count
-   * @access private
-   */
-  private function _fetch_headers($mailbox, $msgs, &$a_msg_headers, $cache_key)
-    {
-    // fetch reqested headers from server
-    $a_header_index = iil_C_FetchHeaders($this->conn, $mailbox, $msgs, false, false, $this->fetch_add_headers);
-
-    if (empty($a_header_index))
-      return 0;
-
-    // cache is incomplete
-    $cache_index = $this->get_message_cache_index($cache_key);
-
-    foreach ($a_header_index as $i => $headers) {
-      if ($this->caching_enabled && $cache_index[$headers->id] != $headers->uid) {
-        // prevent index duplicates
-        if ($cache_index[$headers->id]) {
-          $this->remove_message_cache($cache_key, $headers->id, true);
-          unset($cache_index[$headers->id]);
-          }
-        // add message to cache
-        $this->add_message_cache($cache_key, $headers->id, $headers, NULL,
-          !in_array($headers->uid, $cache_index));
+    /**
+     * Private method for listing a set of threaded message headers (search results)
+     *
+     * @param   string   Mailbox/folder name
+     * @param   int      Current page to list
+     * @param   string   Header field to sort by
+     * @param   string   Sort order [ASC|DESC]
+     * @param   boolean  Number of slice items to extract from result array
+     * @return  array    Indexed array with message header objects
+     * @access  private
+     * @see     rcube_imap::list_header_set()
+     */
+    private function _list_thread_header_set($mailbox, $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
+    {
+        // update search_set if previous data was fetched with disabled threading
+        if (!$this->search_threads)
+            $this->search('', $this->search_string, $this->search_charset, $sort_field);
+
+        $thread_tree = $this->search_set['tree'];
+        $msg_depth = $this->search_set['depth'];
+        $has_children = $this->search_set['children'];
+        $a_msg_headers = array();
+
+        $page = $page ? $page : $this->list_page;
+        $start_msg = ($page-1) * $this->page_size;
+
+        $this->_set_sort_order($sort_field, $sort_order);
+
+        $msg_index = $this->_sort_threads($mailbox, $thread_tree, array_keys($msg_depth));
+
+        return $this->_fetch_thread_headers($mailbox,
+            $thread_tree, $msg_depth, $has_children, $msg_index, $page, $slice=0);
+    }
+
+
+    /**
+     * Helper function to get first and last index of the requested set
+     *
+     * @param  int     message count
+     * @param  mixed   page number to show, or string 'all'
+     * @return array   array with two values: first index, last index
+     * @access private
+     */
+    private function _get_message_range($max, $page)
+    {
+        $start_msg = ($page-1) * $this->page_size;
+    
+        if ($page=='all') {
+            $begin  = 0;
+            $end    = $max;
+        }
+        else if ($this->sort_order=='DESC') {
+            $begin  = $max - $this->page_size - $start_msg;
+            $end    = $max - $start_msg;
+        }
+        else {
+            $begin  = $start_msg;
+            $end    = $start_msg + $this->page_size;
         }
 
-      $a_msg_headers[$headers->uid] = $headers;
-      }
+        if ($begin < 0) $begin = 0;
+        if ($end < 0) $end = $max;
+        if ($end > $max) $end = $max;
+    
+        return array($begin, $end);
+    }
+    
 
-    return count($a_msg_headers);
+    /**
+     * Fetches message headers
+     * Used for loop
+     *
+     * @param  string  Mailbox name
+     * @param  string  Message index to fetch
+     * @param  array   Reference to message headers array
+     * @param  array   Array with cache index
+     * @return int     Messages count
+     * @access private
+     */
+    private function _fetch_headers($mailbox, $msgs, &$a_msg_headers, $cache_key)
+    {
+        // fetch reqested headers from server
+        $a_header_index = $this->conn->fetchHeaders(
+            $mailbox, $msgs, false, false, $this->fetch_add_headers);
+
+        if (empty($a_header_index))
+            return 0;
+
+        // cache is incomplete
+        $cache_index = $this->get_message_cache_index($cache_key);
+
+        foreach ($a_header_index as $i => $headers) {
+            if ($this->caching_enabled && $cache_index[$headers->id] != $headers->uid) {
+                // prevent index duplicates
+                if ($cache_index[$headers->id]) {
+                    $this->remove_message_cache($cache_key, $headers->id, true);
+                    unset($cache_index[$headers->id]);
+                }
+                // add message to cache
+                $this->add_message_cache($cache_key, $headers->id, $headers, NULL,
+                    !in_array($headers->uid, $cache_index));
+            }
+
+            $a_msg_headers[$headers->uid] = $headers;
+        }
+
+        return count($a_msg_headers);
     }
   
-  /**
-   * Fetches IDS of pseudo recent messages.
-   *
-   * We compare the maximum UID to determine the number of
-   * new messages because the RECENT flag is not reliable.
-   *
-   * @param string  Mailbox/folder name
-   * @return array  List of recent message UIDs
-   */
-  function recent_uids($mbox_name = null, $nofetch = false)
-  {
-    $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
-    $old_maxuid = intval($_SESSION['maxuid'][$mailbox]);
-    
-    // refresh message count -> will update $_SESSION['maxuid'][$mailbox]
-    $this->_messagecount($mailbox, 'ALL', true);
-    
-    if ($_SESSION['maxuid'][$mailbox] > $old_maxuid) {
-      $maxuid = max(1, $old_maxuid+1);
-      return array_values((array)iil_C_FetchHeaderIndex($this->conn, $mailbox, "$maxuid:*", 'UID', $this->skip_deleted, true));
-    }
-    
-    return array();
-  }
+    /**
+     * Fetches IDS of pseudo recent messages.
+     *
+     * We compare the maximum UID to determine the number of
+     * new messages because the RECENT flag is not reliable.
+     *
+     * @param string  Mailbox/folder name
+     * @return array  List of recent message UIDs
+     */
+    function recent_uids($mbox_name = null, $nofetch = false)
+    {
+        $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
+        $old_maxuid = intval($_SESSION['maxuid'][$mailbox]);
+    
+        // refresh message count -> will update $_SESSION['maxuid'][$mailbox]
+        $this->_messagecount($mailbox, 'ALL', true);
+    
+        if ($_SESSION['maxuid'][$mailbox] > $old_maxuid) {
+            $maxuid = max(1, $old_maxuid+1);
+            return array_values((array)$this->conn->fetchHeaderIndex(
+                $mailbox, "$maxuid:*", 'UID', $this->skip_deleted, true));
+        }
+    
+        return array();
+    }
   
-  /**
-   * Return sorted array of message IDs (not UIDs)
-   *
-   * @param string Mailbox to get index from
-   * @param string Sort column
-   * @param string Sort order [ASC, DESC]
-   * @return array Indexed array with message ids
-   */
-  function message_index($mbox_name='', $sort_field=NULL, $sort_order=NULL)
-    {
-    if ($this->threading)
-      return $this->thread_index($mbox_name, $sort_field, $sort_order);
+    /**
+     * Return sorted array of message IDs (not UIDs)
+     *
+     * @param string Mailbox to get index from
+     * @param string Sort column
+     * @param string Sort order [ASC, DESC]
+     * @return array Indexed array with message ids
+     */
+    function message_index($mbox_name='', $sort_field=NULL, $sort_order=NULL)
+    {
+        if ($this->threading)
+            return $this->thread_index($mbox_name, $sort_field, $sort_order);
+
+        $this->_set_sort_order($sort_field, $sort_order);
+
+        $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
+        $key = "{$mailbox}:{$this->sort_field}:{$this->sort_order}:{$this->search_string}.msgi";
+
+        // we have a saved search result, get index from there
+        if (!isset($this->cache[$key]) && $this->search_string
+            && !$this->search_threads && $mailbox == $this->mailbox) {
+            // use message index sort as default sorting
+            if (!$this->sort_field) {
+                $msgs = $this->search_set;
+
+                if ($this->search_sort_field != 'date')
+                    sort($msgs);
+
+                if ($this->sort_order == 'DESC')
+                    $this->cache[$key] = array_reverse($msgs);
+                else
+                    $this->cache[$key] = $msgs;
+            }
+            // sort with SORT command
+            else if ($this->get_capability('SORT')) {
+                if ($this->sort_field && $this->search_sort_field != $this->sort_field)
+                    $this->search('', $this->search_string, $this->search_charset, $this->sort_field);
+
+                if ($this->sort_order == 'DESC')
+                    $this->cache[$key] = array_reverse($this->search_set);
+                else
+                    $this->cache[$key] = $this->search_set;
+            }
+            else {
+                $a_index = $this->conn->fetchHeaderIndex($mailbox,
+	                join(',', $this->search_set), $this->sort_field, $this->skip_deleted);
+                
+                if (is_array($a_index)) {
+                    if ($this->sort_order=="ASC")
+                        asort($a_index);
+                    else if ($this->sort_order=="DESC")
+                        arsort($a_index);
+
+                    $this->cache[$key] = array_keys($a_index);
+                }
+                else {
+                    $this->cache[$key] = array();
+                }
+            }
+        }
 
-    $this->_set_sort_order($sort_field, $sort_order);
+        // have stored it in RAM
+        if (isset($this->cache[$key]))
+            return $this->cache[$key];
 
-    $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
-    $key = "{$mailbox}:{$this->sort_field}:{$this->sort_order}:{$this->search_string}.msgi";
+        // check local cache
+        $cache_key = $mailbox.'.msg';
+        $cache_status = $this->check_cache_status($mailbox, $cache_key);
 
-    // we have a saved search result, get index from there
-    if (!isset($this->cache[$key]) && $this->search_string
-      && !$this->search_threads && $mailbox == $this->mailbox)
-    {
-      $this->cache[$key] = array();
-      
-      // use message index sort as default sorting
-      if (!$this->sort_field)
-      {
-        $msgs = $this->search_set;
+        // cache is OK
+        if ($cache_status>0) {
+            $a_index = $this->get_message_cache_index($cache_key,
+                true, $this->sort_field, $this->sort_order);
+            return array_keys($a_index);
+        }
 
-        if ($this->search_sort_field != 'date')
-          sort($msgs);
+        // use message index sort as default sorting
+        if (!$this->sort_field) {
+            if ($this->skip_deleted) {
+                $a_index = $this->_search_index($mailbox, 'ALL');
+            } else if ($max = $this->_messagecount($mailbox)) {
+                $a_index = range(1, $max);
+            }
 
-        if ($this->sort_order == 'DESC')
-          $this->cache[$key] = array_reverse($msgs);
-        else
-          $this->cache[$key] = $msgs;
-      }
-      // sort with SORT command
-      else if ($this->get_capability('SORT'))
-      {
-        if ($this->sort_field && $this->search_sort_field != $this->sort_field)
-          $this->search('', $this->search_string, $this->search_charset, $this->sort_field);
+            if ($this->sort_order == 'DESC')
+                $a_index = array_reverse($a_index);
 
-        if ($this->sort_order == 'DESC')
-          $this->cache[$key] = array_reverse($this->search_set);
-        else
-          $this->cache[$key] = $this->search_set;
-      }
-      else
-      {
-        $a_index = iil_C_FetchHeaderIndex($this->conn, $mailbox,
-	  join(',', $this->search_set), $this->sort_field, $this->skip_deleted);
-
-        if ($this->sort_order=="ASC")
-          asort($a_index);
-        else if ($this->sort_order=="DESC")
-          arsort($a_index);
-
-        $this->cache[$key] = array_keys($a_index);
-      }
-    }
-
-    // have stored it in RAM
-    if (isset($this->cache[$key]))
-      return $this->cache[$key];
-
-    // check local cache
-    $cache_key = $mailbox.'.msg';
-    $cache_status = $this->check_cache_status($mailbox, $cache_key);
-
-    // cache is OK
-    if ($cache_status>0)
-      {
-      $a_index = $this->get_message_cache_index($cache_key, true, $this->sort_field, $this->sort_order);
-      return array_keys($a_index);
-      }
-
-    // use message index sort as default sorting
-    if (!$this->sort_field)
-      {
-      if ($this->skip_deleted) {
-        $a_index = $this->_search_index($mailbox, 'ALL');
-      } else if ($max = $this->_messagecount($mailbox)) {
-        $a_index = range(1, $max);
-      }
-
-      if ($this->sort_order == 'DESC')
-        $a_index = array_reverse($a_index);
-
-      $this->cache[$key] = $a_index;
-      }
-    // fetch complete message index
-    else if ($this->get_capability('SORT'))
-      {
-      if ($a_index = iil_C_Sort($this->conn, $mailbox, $this->sort_field, $this->skip_deleted ? 'UNDELETED' : '')) {
-        if ($this->sort_order == 'DESC')
-          $a_index = array_reverse($a_index);
+            $this->cache[$key] = $a_index;
+        }
+        // fetch complete message index
+        else if ($this->get_capability('SORT')) {
+            if ($a_index = $this->conn->sort($mailbox,
+                $this->sort_field, $this->skip_deleted ? 'UNDELETED' : '')) {
+                if ($this->sort_order == 'DESC')
+                    $a_index = array_reverse($a_index);
 	
-        $this->cache[$key] = $a_index;
-	}
-      }
-    else if ($a_index = iil_C_FetchHeaderIndex($this->conn, $mailbox, "1:*", $this->sort_field, $this->skip_deleted)) {
-      if ($this->sort_order=="ASC")
-        asort($a_index);
-      else if ($this->sort_order=="DESC")
-        arsort($a_index);
+                $this->cache[$key] = $a_index;
+	        }
+        }
+        else if ($a_index = $this->conn->fetchHeaderIndex(
+            $mailbox, "1:*", $this->sort_field, $this->skip_deleted)) {
+            if ($this->sort_order=="ASC")
+                asort($a_index);
+            else if ($this->sort_order=="DESC")
+                arsort($a_index);
         
-      $this->cache[$key] = array_keys($a_index);
-      }
+            $this->cache[$key] = array_keys($a_index);
+        }
 
-    return $this->cache[$key];
+        return $this->cache[$key];
     }
 
 
-  /**
-   * Return sorted array of threaded message IDs (not UIDs)
-   *
-   * @param string Mailbox to get index from
-   * @param string Sort column
-   * @param string Sort order [ASC, DESC]
-   * @return array Indexed array with message IDs
-   */
-  function thread_index($mbox_name='', $sort_field=NULL, $sort_order=NULL)
+    /**
+     * Return sorted array of threaded message IDs (not UIDs)
+     *
+     * @param string Mailbox to get index from
+     * @param string Sort column
+     * @param string Sort order [ASC, DESC]
+     * @return array Indexed array with message IDs
+     */
+    function thread_index($mbox_name='', $sort_field=NULL, $sort_order=NULL)
     {
-    $this->_set_sort_order($sort_field, $sort_order);
+        $this->_set_sort_order($sort_field, $sort_order);
 
-    $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
-    $key = "{$mailbox}:{$this->sort_field}:{$this->sort_order}:{$this->search_string}.thi";
+        $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
+        $key = "{$mailbox}:{$this->sort_field}:{$this->sort_order}:{$this->search_string}.thi";
 
-    // we have a saved search result, get index from there
-    if (!isset($this->cache[$key]) && $this->search_string
-      && $this->search_threads && $mailbox == $this->mailbox)
-    {
-      // use message IDs for better performance
-      $ids = array_keys_recursive($this->search_set['tree']);
-      $this->cache[$key] = $this->_flatten_threads($mailbox, $this->search_set['tree'], $ids);
-    }
+        // we have a saved search result, get index from there
+        if (!isset($this->cache[$key]) && $this->search_string
+            && $this->search_threads && $mailbox == $this->mailbox) {
+            // use message IDs for better performance
+            $ids = array_keys_recursive($this->search_set['tree']);
+            $this->cache[$key] = $this->_flatten_threads($mailbox, $this->search_set['tree'], $ids);
+        }
 
-    // have stored it in RAM
-    if (isset($this->cache[$key]))
-      return $this->cache[$key];
+        // have stored it in RAM
+        if (isset($this->cache[$key]))
+            return $this->cache[$key];
 /*
-    // check local cache
-    $cache_key = $mailbox.'.msg';
-    $cache_status = $this->check_cache_status($mailbox, $cache_key);
-
-    // cache is OK
-    if ($cache_status>0)
-      {
-      $a_index = $this->get_message_cache_index($cache_key, true, $this->sort_field, $this->sort_order);
-      return array_keys($a_index);
-      }
+        // check local cache
+        $cache_key = $mailbox.'.msg';
+        $cache_status = $this->check_cache_status($mailbox, $cache_key);
+
+        // cache is OK
+        if ($cache_status>0) {
+            $a_index = $this->get_message_cache_index($cache_key, true, $this->sort_field, $this->sort_order);
+            return array_keys($a_index);
+        }
 */
-    // get all threads (default sort order)
-    list ($thread_tree) = $this->_fetch_threads($mailbox);
+        // get all threads (default sort order)
+        list ($thread_tree) = $this->_fetch_threads($mailbox);
 
-    $this->cache[$key] = $this->_flatten_threads($mailbox, $thread_tree);
+        $this->cache[$key] = $this->_flatten_threads($mailbox, $thread_tree);
     
-    return $this->cache[$key];
+        return $this->cache[$key];
     }
 
 
-  /**
-   * Return array of threaded messages (all, not only roots)
-   *
-   * @param string Mailbox to get index from
-   * @param array  Threaded messages array (see _fetch_threads())
-   * @param array  Message IDs if we know what we need (e.g. search result)
-   *               for better performance
-   * @return array Indexed array with message IDs
-   *
-   * @access private
-   */
-  private function _flatten_threads($mailbox, $thread_tree, $ids=null)
+    /**
+     * Return array of threaded messages (all, not only roots)
+     *
+     * @param string Mailbox to get index from
+     * @param array  Threaded messages array (see _fetch_threads())
+     * @param array  Message IDs if we know what we need (e.g. search result)
+     *               for better performance
+     * @return array Indexed array with message IDs
+     *
+     * @access private
+     */
+    private function _flatten_threads($mailbox, $thread_tree, $ids=null)
     {
-    if (empty($thread_tree))
-      return array();
+        if (empty($thread_tree))
+            return array();
 
-    $msg_index = $this->_sort_threads($mailbox, $thread_tree, $ids);
+        $msg_index = $this->_sort_threads($mailbox, $thread_tree, $ids);
 
-    if ($this->sort_order == 'DESC')
-      $msg_index = array_reverse($msg_index);
+        if ($this->sort_order == 'DESC')
+            $msg_index = array_reverse($msg_index);
 	  
-    // flatten threads array
-    $all_ids = array();
-    foreach($msg_index as $root) {
-      $all_ids[] = $root;
-      if (!empty($thread_tree[$root]))
-        $all_ids = array_merge($all_ids, array_keys_recursive($thread_tree[$root]));
-      }
+        // flatten threads array
+        $all_ids = array();
+        foreach($msg_index as $root) {
+            $all_ids[] = $root;
+            if (!empty($thread_tree[$root]))
+                $all_ids = array_merge($all_ids, array_keys_recursive($thread_tree[$root]));
+        }
 
-    return $all_ids;
+        return $all_ids;
     }
 
 
-  /**
-   * @access private
-   */
-  private function sync_header_index($mailbox)
+    /**
+     * @access private
+     */
+    private function sync_header_index($mailbox)
     {
-    $cache_key = $mailbox.'.msg';
-    $cache_index = $this->get_message_cache_index($cache_key);
+        $cache_key = $mailbox.'.msg';
+        $cache_index = $this->get_message_cache_index($cache_key);
 
-    // fetch complete message index
-    $a_message_index = iil_C_FetchHeaderIndex($this->conn, $mailbox, "1:*", 'UID', $this->skip_deleted);
+        // fetch complete message index
+        $a_message_index = $this->conn->fetchHeaderIndex($mailbox, "1:*", 'UID', $this->skip_deleted);
     
-    if ($a_message_index === false)
-      return false;
+        if ($a_message_index === false)
+            return false;
         
-    foreach ($a_message_index as $id => $uid)
-      {
-      // message in cache at correct position
-      if ($cache_index[$id] == $uid)
-        {
-        unset($cache_index[$id]);
-        continue;
-        }
-        
-      // message in cache but in wrong position
-      if (in_array((string)$uid, $cache_index, true))
-        {
-        unset($cache_index[$id]);
-        }
+        foreach ($a_message_index as $id => $uid) {
+            // message in cache at correct position
+            if ($cache_index[$id] == $uid) {
+                unset($cache_index[$id]);
+                continue;
+            }
+
+            // message in cache but in wrong position
+            if (in_array((string)$uid, $cache_index, true)) {
+                unset($cache_index[$id]);
+            }
       
-      // other message at this position
-      if (isset($cache_index[$id]))
-        {
-        $for_remove[] = $cache_index[$id];
-        unset($cache_index[$id]);
-        }
+            // other message at this position
+            if (isset($cache_index[$id])) {
+                $for_remove[] = $cache_index[$id];
+                unset($cache_index[$id]);
+            }
         
-        $for_update[] = $id;
-      }
-
-    // clear messages at wrong positions and those deleted that are still in cache_index      
-    if (!empty($for_remove))
-      $cache_index = array_merge($cache_index, $for_remove);
-    
-    if (!empty($cache_index))
-      $this->remove_message_cache($cache_key, $cache_index);
-
-    // fetch complete headers and add to cache
-    if (!empty($for_update)) {
-      if ($headers = iil_C_FetchHeader($this->conn, $mailbox, join(',', $for_update), false, $this->fetch_add_headers))
-        foreach ($headers as $header)
-          $this->add_message_cache($cache_key, $header->id, $header, NULL,
-            in_array($header->uid, (array)$for_remove));
-      }
-    }
-
-
-  /**
-   * Invoke search request to IMAP server
-   *
-   * @param  string  mailbox name to search in
-   * @param  string  search string
-   * @param  string  search string charset
-   * @param  string  header field to sort by
-   * @return array   search results as list of message ids
-   * @access public
-   */
-  function search($mbox_name='', $str=NULL, $charset=NULL, $sort_field=NULL)
-    {
-    if (!$str)
-      return false;
-    
-    $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
-
-    $results = $this->_search_index($mailbox, $str, $charset, $sort_field);
-
-    // try search with US-ASCII charset (should be supported by server)
-    // only if UTF-8 search is not supported
-    if (empty($results) && !is_array($results) && !empty($charset) && $charset != 'US-ASCII')
-    {
-      // convert strings to US_ASCII
-      if(preg_match_all('/\{([0-9]+)\}\r\n/', $str, $matches, PREG_OFFSET_CAPTURE))
-      {
-        $last = 0; $res = '';
-        foreach($matches[1] as $m)
-        {
-          $string_offset = $m[1] + strlen($m[0]) + 4; // {}\r\n
-          $string = substr($str, $string_offset - 1, $m[0]);
-          $string = rcube_charset_convert($string, $charset, 'US-ASCII');
-          if (!$string) continue;
-          $res .= sprintf("%s{%d}\r\n%s", substr($str, $last, $m[1] - $last - 1), strlen($string), $string);
-          $last = $m[0] + $string_offset - 1;
+            $for_update[] = $id;
         }
-        if ($last < strlen($str))
-          $res .= substr($str, $last, strlen($str)-$last);
-      }
-      else // strings for conversion not found
-      $res = $str;
 
-      $results = $this->search($mbox_name, $res, NULL, $sort_field);
+        // clear messages at wrong positions and those deleted that are still in cache_index      
+        if (!empty($for_remove))
+            $cache_index = array_merge($cache_index, $for_remove);
+    
+        if (!empty($cache_index))
+            $this->remove_message_cache($cache_key, $cache_index);
+
+        // fetch complete headers and add to cache
+        if (!empty($for_update)) {
+            if ($headers = $this->conn->fetchHeader($mailbox,
+                    join(',', $for_update), false, $this->fetch_add_headers)) {
+                foreach ($headers as $header) {
+                    $this->add_message_cache($cache_key, $header->id, $header, NULL,
+                        in_array($header->uid, (array)$for_remove));
+                }
+            }
+        }
     }
 
-    $this->set_search_set($str, $results, $charset, $sort_field, (bool)$this->threading);
 
-    return $results;
+    /**
+     * Invoke search request to IMAP server
+     *
+     * @param  string  mailbox name to search in
+     * @param  string  search string
+     * @param  string  search string charset
+     * @param  string  header field to sort by
+     * @return array   search results as list of message ids
+     * @access public
+     */
+    function search($mbox_name='', $str=NULL, $charset=NULL, $sort_field=NULL)
+    {
+        if (!$str)
+            return false;
+    
+        $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
+
+        $results = $this->_search_index($mailbox, $str, $charset, $sort_field);
+
+        // try search with US-ASCII charset (should be supported by server)
+        // only if UTF-8 search is not supported
+        if (empty($results) && !is_array($results) && !empty($charset) && $charset != 'US-ASCII')
+        {
+            // convert strings to US_ASCII
+            if(preg_match_all('/\{([0-9]+)\}\r\n/', $str, $matches, PREG_OFFSET_CAPTURE)) {
+                $last = 0; $res = '';
+                foreach($matches[1] as $m)
+                {
+                    $string_offset = $m[1] + strlen($m[0]) + 4; // {}\r\n
+                    $string = substr($str, $string_offset - 1, $m[0]);
+                    $string = rcube_charset_convert($string, $charset, 'US-ASCII');
+                    if (!$string)
+                        continue;
+                    $res .= sprintf("%s{%d}\r\n%s", substr($str, $last, $m[1] - $last - 1), strlen($string), $string);
+                    $last = $m[0] + $string_offset - 1;
+                }
+                if ($last < strlen($str))
+                    $res .= substr($str, $last, strlen($str)-$last);
+            }
+            else // strings for conversion not found
+                $res = $str;
+
+            $results = $this->search($mbox_name, $res, NULL, $sort_field);
+        }
+
+        $this->set_search_set($str, $results, $charset, $sort_field, (bool)$this->threading);
+
+        return $results;
     }
 
 
-  /**
-   * Private search method
-   *
-   * @return array   search results as list of message ids
-   * @access private
-   * @see rcube_imap::search()
-   */
-  private function _search_index($mailbox, $criteria='ALL', $charset=NULL, $sort_field=NULL)
+    /**
+     * Private search method
+     *
+     * @return array   search results as list of message ids
+     * @access private
+     * @see rcube_imap::search()
+     */
+    private function _search_index($mailbox, $criteria='ALL', $charset=NULL, $sort_field=NULL)
     {
-    $orig_criteria = $criteria;
+        $orig_criteria = $criteria;
 
-    if ($this->skip_deleted && !preg_match('/UNDELETED/', $criteria))
-      $criteria = 'UNDELETED '.$criteria;
+        if ($this->skip_deleted && !preg_match('/UNDELETED/', $criteria))
+            $criteria = 'UNDELETED '.$criteria;
 
-    if ($this->threading) {
-      list ($thread_tree, $msg_depth, $has_children) = iil_C_Thread($this->conn,
-            $mailbox, $this->threading, $criteria, $charset);
+        if ($this->threading) {
+            list ($thread_tree, $msg_depth, $has_children) = $this->conn->thread(
+                $mailbox, $this->threading, $criteria, $charset);
 
-      $a_messages = array(
-        'tree' 	=> $thread_tree,
-	'depth'	=> $msg_depth,
-	'children' => $has_children
-        );
-      }
-    else if ($sort_field && $this->get_capability('SORT')) {
-      $charset = $charset ? $charset : $this->default_charset;
-      $a_messages = iil_C_Sort($this->conn, $mailbox, $sort_field, $criteria, false, $charset);
-
-      if (!$a_messages)
-	return array();
-      }
-    else {
-      if ($orig_criteria == 'ALL') {
-        $max = $this->_messagecount($mailbox);
-        $a_messages = $max ? range(1, $max) : array();
-        }
-      else {
-        $a_messages = iil_C_Search($this->conn, $mailbox, ($charset ? "CHARSET $charset " : '') . $criteria);
-
-	if (!$a_messages)
-	  return array();
-
-        // I didn't found that SEARCH always returns sorted IDs
-        if (!$this->sort_field)
-          sort($a_messages);
-        }
-      }
-    // update messagecount cache ?
-//    $a_mailbox_cache = get_cache('messagecount');
-//    $a_mailbox_cache[$mailbox][$criteria] = sizeof($a_messages);
-//    $this->update_cache('messagecount', $a_mailbox_cache);
+            $a_messages = array(
+                'tree' 	=> $thread_tree,
+	            'depth'	=> $msg_depth,
+	            'children' => $has_children
+            );
+        }
+        else if ($sort_field && $this->get_capability('SORT')) {
+            $charset = $charset ? $charset : $this->default_charset;
+            $a_messages = $this->conn->sort($mailbox, $sort_field, $criteria, false, $charset);
+
+            if (!$a_messages)
+	            return array();
+        }
+        else {
+            if ($orig_criteria == 'ALL') {
+                $max = $this->_messagecount($mailbox);
+                $a_messages = $max ? range(1, $max) : array();
+            }
+            else {
+                $a_messages = $this->conn->search($mailbox,
+                        ($charset ? "CHARSET $charset " : '') . $criteria);
+
+	        if (!$a_messages)
+	            return array();
+
+            // I didn't found that SEARCH always returns sorted IDs
+            if (!$this->sort_field)
+                sort($a_messages);
+            }
+        }
+
+        // update messagecount cache ?
+//      $a_mailbox_cache = get_cache('messagecount');
+//      $a_mailbox_cache[$mailbox][$criteria] = sizeof($a_messages);
+//      $this->update_cache('messagecount', $a_mailbox_cache);
         
-    return $a_messages;
+        return $a_messages;
     }
     
   
-  /**
-   * Sort thread
-   *
-   * @param string Mailbox name
-   * @param  array Unsorted thread tree (iil_C_Thread() result)
-   * @param  array Message IDs if we know what we need (e.g. search result)
-   * @return array Sorted roots IDs
-   * @access private
-   */
-  private function _sort_threads($mailbox, $thread_tree, $ids=NULL)
-    {
-    // THREAD=ORDEREDSUBJECT: 	sorting by sent date of root message
-    // THREAD=REFERENCES: 	sorting by sent date of root message
-    // THREAD=REFS: 		sorting by the most recent date in each thread
-    // default sorting
-    if (!$this->sort_field || ($this->sort_field == 'date' && $this->threading == 'REFS')) {
-        return array_keys((array)$thread_tree);
-      }
-    // here we'll implement REFS sorting, for performance reason
-    else { // ($sort_field == 'date' && $this->threading != 'REFS')
-      // use SORT command
-      if ($this->get_capability('SORT')) {
-        $a_index = iil_C_Sort($this->conn, $mailbox, $this->sort_field,
-	    !empty($ids) ? $ids : ($this->skip_deleted ? 'UNDELETED' : ''));
-
-	// return unsorted tree if we've got no index data
-	if (!$a_index)
-	  return array_keys((array)$thread_tree);
-        }
-      else {
-        // fetch specified headers for all messages and sort them
-        $a_index = iil_C_FetchHeaderIndex($this->conn, $mailbox, !empty($ids) ? $ids : "1:*",
-	    $this->sort_field, $this->skip_deleted);
-
-	// return unsorted tree if we've got no index data
-	if (!$a_index)
-	  return array_keys((array)$thread_tree);
-
-        asort($a_index); // ASC
-	$a_index = array_values($a_index);
-        }
-
-	return $this->_sort_thread_refs($thread_tree, $a_index);
-      }
-    }
-
-
-  /**
-   * THREAD=REFS sorting implementation
-   *
-   * @param  array   Thread tree array (message identifiers as keys)
-   * @param  array   Array of sorted message identifiers
-   * @return array   Array of sorted roots messages
-   * @access private
-   */
-  private function _sort_thread_refs($tree, $index)
-    {
-    if (empty($tree))
-      return array();
-    
-    $index = array_combine(array_values($index), $index);
-
-    // assign roots
-    foreach ($tree as $idx => $val) {
-      $index[$idx] = $idx;
-      if (!empty($val)) {
-        $idx_arr = array_keys_recursive($tree[$idx]);
-        foreach ($idx_arr as $subidx)
-          $index[$subidx] = $idx;
-        }
-      }
-
-    $index = array_values($index);  
-
-    // create sorted array of roots
-    $msg_index = array();
-    if ($this->sort_order != 'DESC') {
-      foreach ($index as $idx)
-        if (!isset($msg_index[$idx]))
-          $msg_index[$idx] = $idx;
-      $msg_index = array_values($msg_index);
-      }
-    else {
-      for ($x=count($index)-1; $x>=0; $x--)
-        if (!isset($msg_index[$index[$x]]))
-          $msg_index[$index[$x]] = $index[$x];
-      $msg_index = array_reverse($msg_index);
-      }
-
-    return $msg_index;
-    }
-
-
-  /**
-   * Refresh saved search set
-   *
-   * @return array Current search set
-   */
-  function refresh_search()
-    {
-    if (!empty($this->search_string))
-      $this->search_set = $this->search('', $this->search_string, $this->search_charset,
-    	    $this->search_sort_field, $this->search_threads);
+    /**
+     * Sort thread
+     *
+     * @param string Mailbox name
+     * @param  array Unsorted thread tree (rcube_imap_generic::thread() result)
+     * @param  array Message IDs if we know what we need (e.g. search result)
+     * @return array Sorted roots IDs
+     * @access private
+     */
+    private function _sort_threads($mailbox, $thread_tree, $ids=NULL)
+    {
+        // THREAD=ORDEREDSUBJECT: 	sorting by sent date of root message
+        // THREAD=REFERENCES: 	sorting by sent date of root message
+        // THREAD=REFS: 		sorting by the most recent date in each thread
+        // default sorting
+        if (!$this->sort_field || ($this->sort_field == 'date' && $this->threading == 'REFS')) {
+            return array_keys((array)$thread_tree);
+          }
+        // here we'll implement REFS sorting, for performance reason
+        else { // ($sort_field == 'date' && $this->threading != 'REFS')
+            // use SORT command
+            if ($this->get_capability('SORT')) {
+                $a_index = $this->conn->sort($mailbox, $this->sort_field,
+	                !empty($ids) ? $ids : ($this->skip_deleted ? 'UNDELETED' : ''));
+
+	            // return unsorted tree if we've got no index data
+	            if (!$a_index)
+	                return array_keys((array)$thread_tree);
+            }
+            else {
+                // fetch specified headers for all messages and sort them
+                $a_index = $this->conn->fetchHeaderIndex($mailbox, !empty($ids) ? $ids : "1:*",
+	                $this->sort_field, $this->skip_deleted);
+
+	            // return unsorted tree if we've got no index data
+	            if (!$a_index)
+	                return array_keys((array)$thread_tree);
+
+                asort($a_index); // ASC
+	            $a_index = array_values($a_index);
+            }
+
+	        return $this->_sort_thread_refs($thread_tree, $a_index);
+        }
+    }
+
+
+    /**
+     * THREAD=REFS sorting implementation
+     *
+     * @param  array   Thread tree array (message identifiers as keys)
+     * @param  array   Array of sorted message identifiers
+     * @return array   Array of sorted roots messages
+     * @access private
+     */
+    private function _sort_thread_refs($tree, $index)
+    {
+        if (empty($tree))
+            return array();
+    
+        $index = array_combine(array_values($index), $index);
+
+        // assign roots
+        foreach ($tree as $idx => $val) {
+            $index[$idx] = $idx;
+            if (!empty($val)) {
+                $idx_arr = array_keys_recursive($tree[$idx]);
+                foreach ($idx_arr as $subidx)
+                    $index[$subidx] = $idx;
+            }
+        }
+
+        $index = array_values($index);  
+
+        // create sorted array of roots
+        $msg_index = array();
+        if ($this->sort_order != 'DESC') {
+            foreach ($index as $idx)
+                if (!isset($msg_index[$idx]))
+                    $msg_index[$idx] = $idx;
+            $msg_index = array_values($msg_index);
+        }
+        else {
+            for ($x=count($index)-1; $x>=0; $x--)
+                if (!isset($msg_index[$index[$x]]))
+                    $msg_index[$index[$x]] = $index[$x];
+            $msg_index = array_reverse($msg_index);
+        }
+
+        return $msg_index;
+    }
+
+
+    /**
+     * Refresh saved search set
+     *
+     * @return array Current search set
+     */
+    function refresh_search()
+    {
+        if (!empty($this->search_string))
+            $this->search_set = $this->search('', $this->search_string, $this->search_charset,
+
+    	$this->search_sort_field, $this->search_threads);
       
-    return $this->get_search_set();
+        return $this->get_search_set();
     }
   
   
-  /**
-   * Check if the given message ID is part of the current search set
-   *
-   * @return boolean True on match or if no search request is stored
-   */
-  function in_searchset($msgid)
-  {
-    if (!empty($this->search_string))
-      return in_array("$msgid", (array)$this->search_set, true);
-    else
-      return true;
-  }
-
-
-  /**
-   * Return message headers object of a specific message
-   *
-   * @param int     Message ID
-   * @param string  Mailbox to read from 
-   * @param boolean True if $id is the message UID
-   * @param boolean True if we need also BODYSTRUCTURE in headers
-   * @return object Message headers representation
-   */
-  function get_headers($id, $mbox_name=NULL, $is_uid=true, $bodystr=false)
-    {
-    $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
-    $uid = $is_uid ? $id : $this->_id2uid($id);
-
-    // get cached headers
-    if ($uid && ($headers = &$this->get_cached_message($mailbox.'.msg', $uid)))
-      return $headers;
-
-    $headers = iil_C_FetchHeader($this->conn, $mailbox, $id, $is_uid, $bodystr, $this->fetch_add_headers);
-
-    // write headers cache
-    if ($headers)
-      {
-      if ($headers->uid && $headers->id)
-        $this->uid_id_map[$mailbox][$headers->uid] = $headers->id;
-
-      $this->add_message_cache($mailbox.'.msg', $headers->id, $headers, NULL, true);
-      }
-
-    return $headers;
-    }
-
-
-  /**
-   * Fetch body structure from the IMAP server and build
-   * an object structure similar to the one generated by PEAR::Mail_mimeDecode
-   *
-   * @param int Message UID to fetch
-   * @param string Message BODYSTRUCTURE string (optional)
-   * @return object rcube_message_part Message part tree or False on failure
-   */
-  function &get_structure($uid, $structure_str='')
-    {
-    $cache_key = $this->mailbox.'.msg';
-    $headers = &$this->get_cached_message($cache_key, $uid);
-
-    // return cached message structure
-    if (is_object($headers) && is_object($headers->structure)) {
-      return $headers->structure;
-    }
-
-    if (!$structure_str)
-      $structure_str = iil_C_FetchStructureString($this->conn, $this->mailbox, $uid, true);
-    $structure = iml_GetRawStructureArray($structure_str);
-    $struct = false;
-
-    // parse structure and add headers
-    if (!empty($structure))
-      {
-      $headers = $this->get_headers($uid);
-      $this->_msg_id = $headers->id;
-
-      // set message charset from message headers
-      if ($headers->charset)
-        $this->struct_charset = $headers->charset;
-      else
-        $this->struct_charset = $this->_structure_charset($structure);
-
-      // Here we can recognize malformed BODYSTRUCTURE and 
-      // 1. [@TODO] parse the message in other way to create our own message structure
-      // 2. or just show the raw message body.
-      // Example of structure for malformed MIME message:
-      // ("text" "plain" ("charset" "us-ascii") NIL NIL "7bit" 2154 70 NIL NIL NIL)
-      if ($headers->ctype && $headers->ctype != 'text/plain'
-          && $structure[0] == 'text' && $structure[1] == 'plain') {
-        return false;
-      }
+    /**
+     * Check if the given message ID is part of the current search set
+     *
+     * @return boolean True on match or if no search request is stored
+     */
+    function in_searchset($msgid)
+    {
+        if (!empty($this->search_string)) {
+            if ($this->search_threads)
+                return isset($this->search_set['depth']["$msgid"]);
+            else
+                return in_array("$msgid", (array)$this->search_set, true);
+        }
+        else
+            return true;
+    }
 
-      $struct = &$this->_structure_part($structure);
-      $struct->headers = get_object_vars($headers);
 
-      // don't trust given content-type
-      if (empty($struct->parts) && !empty($struct->headers['ctype']))
-        {
-        $struct->mime_id = '1';
-        $struct->mimetype = strtolower($struct->headers['ctype']);
-        list($struct->ctype_primary, $struct->ctype_secondary) = explode('/', $struct->mimetype);
+    /**
+     * Return message headers object of a specific message
+     *
+     * @param int     Message ID
+     * @param string  Mailbox to read from 
+     * @param boolean True if $id is the message UID
+     * @param boolean True if we need also BODYSTRUCTURE in headers
+     * @return object Message headers representation
+     */
+    function get_headers($id, $mbox_name=NULL, $is_uid=true, $bodystr=false)
+    {
+        $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
+        $uid = $is_uid ? $id : $this->_id2uid($id);
+
+        // get cached headers
+        if ($uid && ($headers = &$this->get_cached_message($mailbox.'.msg', $uid)))
+            return $headers;
+
+        $headers = $this->conn->fetchHeader(
+            $mailbox, $id, $is_uid, $bodystr, $this->fetch_add_headers);
+
+        // write headers cache
+        if ($headers) {
+            if ($headers->uid && $headers->id)
+                $this->uid_id_map[$mailbox][$headers->uid] = $headers->id;
+
+            $this->add_message_cache($mailbox.'.msg', $headers->id, $headers, NULL, true);
+        }
+
+        return $headers;
+    }
+
+
+    /**
+     * Fetch body structure from the IMAP server and build
+     * an object structure similar to the one generated by PEAR::Mail_mimeDecode
+     *
+     * @param int Message UID to fetch
+     * @param string Message BODYSTRUCTURE string (optional)
+     * @return object rcube_message_part Message part tree or False on failure
+     */
+    function &get_structure($uid, $structure_str='')
+    {
+        $cache_key = $this->mailbox.'.msg';
+        $headers = &$this->get_cached_message($cache_key, $uid);
+
+        // return cached message structure
+        if (is_object($headers) && is_object($headers->structure)) {
+            return $headers->structure;
+        }
+
+        if (!$structure_str)
+            $structure_str = $this->conn->fetchStructureString($this->mailbox, $uid, true);
+        $structure = iml_GetRawStructureArray($structure_str);
+        $struct = false;
+
+        // parse structure and add headers
+        if (!empty($structure)) {
+            $headers = $this->get_headers($uid);
+            $this->_msg_id = $headers->id;
+
+        // set message charset from message headers
+        if ($headers->charset)
+            $this->struct_charset = $headers->charset;
+        else
+            $this->struct_charset = $this->_structure_charset($structure);
+
+        // Here we can recognize malformed BODYSTRUCTURE and 
+        // 1. [@TODO] parse the message in other way to create our own message structure
+        // 2. or just show the raw message body.
+        // Example of structure for malformed MIME message:
+        // ("text" "plain" ("charset" "us-ascii") NIL NIL "7bit" 2154 70 NIL NIL NIL)
+        if ($headers->ctype && $headers->ctype != 'text/plain'
+            && $structure[0] == 'text' && $structure[1] == 'plain') {
+            return false;
         }
 
-      // write structure to cache
-      if ($this->caching_enabled)
-        $this->add_message_cache($cache_key, $this->_msg_id, $headers, $struct);
-      }
+        $struct = &$this->_structure_part($structure);
+        $struct->headers = get_object_vars($headers);
+
+        // don't trust given content-type
+        if (empty($struct->parts) && !empty($struct->headers['ctype'])) {
+            $struct->mime_id = '1';
+            $struct->mimetype = strtolower($struct->headers['ctype']);
+            list($struct->ctype_primary, $struct->ctype_secondary) = explode('/', $struct->mimetype);
+        }
+
+        // write structure to cache
+        if ($this->caching_enabled)
+            $this->add_message_cache($cache_key, $this->_msg_id, $headers, $struct);
+        }
 
-    return $struct;
+        return $struct;
     }
 
   
-  /**
-   * Build message part object
-   *
-   * @access private
-   */
-  function &_structure_part($part, $count=0, $parent='', $mime_headers=null, $raw_headers=null)
-    {
-    $struct = new rcube_message_part;
-    $struct->mime_id = empty($parent) ? (string)$count : "$parent.$count";
-
-    // multipart
-    if (is_array($part[0]))
-      {
-      $struct->ctype_primary = 'multipart';
+    /**
+     * Build message part object
+     *
+     * @access private
+     */
+    function &_structure_part($part, $count=0, $parent='', $mime_headers=null, $raw_headers=null)
+    {
+        $struct = new rcube_message_part;
+        $struct->mime_id = empty($parent) ? (string)$count : "$parent.$count";
+
+        // multipart
+        if (is_array($part[0])) {
+            $struct->ctype_primary = 'multipart';
       
-      // find first non-array entry
-      for ($i=1; $i<count($part); $i++)
-        if (!is_array($part[$i]))
-          {
-          $struct->ctype_secondary = strtolower($part[$i]);
-          break;
-          }
-          
-      $struct->mimetype = 'multipart/'.$struct->ctype_secondary;
-
-      // build parts list for headers pre-fetching
-      for ($i=0, $count=0; $i<count($part); $i++)
-        if (is_array($part[$i]) && count($part[$i]) > 3) {
-          // fetch message headers if message/rfc822 or named part (could contain Content-Location header)
-          if (!is_array($part[$i][0])) {
-            $tmp_part_id = $struct->mime_id ? $struct->mime_id.'.'.($i+1) : $i+1;
-            if (strtolower($part[$i][0]) == 'message' && strtolower($part[$i][1]) == 'rfc822') {
-              $raw_part_headers[] = $tmp_part_id;
-              $mime_part_headers[] = $tmp_part_id;
+            // find first non-array entry
+            for ($i=1; $i<count($part); $i++) {
+                if (!is_array($part[$i])) {
+                    $struct->ctype_secondary = strtolower($part[$i]);
+                    break;
+                }
             }
-            else if (in_array('name', (array)$part[$i][2]) && (empty($part[$i][3]) || $part[$i][3]=='NIL')) {
-              $mime_part_headers[] = $tmp_part_id;
+            
+            $struct->mimetype = 'multipart/'.$struct->ctype_secondary;
+
+            // build parts list for headers pre-fetching
+            for ($i=0, $count=0; $i<count($part); $i++) {
+                if (is_array($part[$i]) && count($part[$i]) > 3) {
+                    // fetch message headers if message/rfc822
+                    // or named part (could contain Content-Location header)
+                    if (!is_array($part[$i][0])) {
+                        $tmp_part_id = $struct->mime_id ? $struct->mime_id.'.'.($i+1) : $i+1;
+                        if (strtolower($part[$i][0]) == 'message' && strtolower($part[$i][1]) == 'rfc822') {
+                            $raw_part_headers[] = $tmp_part_id;
+                            $mime_part_headers[] = $tmp_part_id;
+                        }
+                        else if (in_array('name', (array)$part[$i][2]) && (empty($part[$i][3]) || $part[$i][3]=='NIL')) {
+                            $mime_part_headers[] = $tmp_part_id;
+                        }
+                    }
+                }
             }
-          }
-        }
         
-      // pre-fetch headers of all parts (in one command for better performance)
-      // @TODO: we could do this before _structure_part() call, to fetch
-      // headers for parts on all levels
-      if ($mime_part_headers)
-        $mime_part_headers = iil_C_FetchMIMEHeaders($this->conn, $this->mailbox,
-          $this->_msg_id, $mime_part_headers);
-      // we'll need a real content-type of message/rfc822 part
-      if ($raw_part_headers)
-        $raw_part_headers = iil_C_FetchMIMEHeaders($this->conn, $this->mailbox,
-          $this->_msg_id, $raw_part_headers, false);
-
-      $struct->parts = array();
-      for ($i=0, $count=0; $i<count($part); $i++)
-        if (is_array($part[$i]) && count($part[$i]) > 3) {
-          $tmp_part_id = $struct->mime_id ? $struct->mime_id.'.'.($i+1) : $i+1;
-          $struct->parts[] = $this->_structure_part($part[$i], ++$count, $struct->mime_id,
-            $mime_part_headers[$tmp_part_id], $raw_part_headers[$tmp_part_id]);
-        }
-
-      return $struct;
-      }
-
-
-    // regular part
-    $struct->ctype_primary = strtolower($part[0]);
-    $struct->ctype_secondary = strtolower($part[1]);
-    $struct->mimetype = $struct->ctype_primary.'/'.$struct->ctype_secondary;
-
-    // read content type parameters
-    if (is_array($part[2]))
-      {
-      $struct->ctype_parameters = array();
-      for ($i=0; $i<count($part[2]); $i+=2)
-        $struct->ctype_parameters[strtolower($part[2][$i])] = $part[2][$i+1];
+            // pre-fetch headers of all parts (in one command for better performance)
+            // @TODO: we could do this before _structure_part() call, to fetch
+            // headers for parts on all levels
+            if ($mime_part_headers) {
+                $mime_part_headers = $this->conn->fetchMIMEHeaders($this->mailbox,
+                    $this->_msg_id, $mime_part_headers);
+            }
+            // we'll need a real content-type of message/rfc822 part
+            if ($raw_part_headers) {
+                $raw_part_headers = $this->conn->fetchMIMEHeaders($this->mailbox,
+                    $this->_msg_id, $raw_part_headers, false);
+            }
+            $struct->parts = array();
+            for ($i=0, $count=0; $i<count($part); $i++) {
+                if (is_array($part[$i]) && count($part[$i]) > 3) {
+                    $tmp_part_id = $struct->mime_id ? $struct->mime_id.'.'.($i+1) : $i+1;
+                    $struct->parts[] = $this->_structure_part($part[$i], ++$count, $struct->mime_id,
+                    $mime_part_headers[$tmp_part_id], $raw_part_headers[$tmp_part_id]);
+                }
+            }
+
+            return $struct;
+        }
+
+        // regular part
+        $struct->ctype_primary = strtolower($part[0]);
+        $struct->ctype_secondary = strtolower($part[1]);
+        $struct->mimetype = $struct->ctype_primary.'/'.$struct->ctype_secondary;
+
+        // read content type parameters
+        if (is_array($part[2])) {
+            $struct->ctype_parameters = array();
+            for ($i=0; $i<count($part[2]); $i+=2)
+                $struct->ctype_parameters[strtolower($part[2][$i])] = $part[2][$i+1];
         
-      if (isset($struct->ctype_parameters['charset']))
-        $struct->charset = $struct->ctype_parameters['charset'];
-      }
-    
-    // read content encoding
-    if (!empty($part[5]) && $part[5]!='NIL')
-      {
-      $struct->encoding = strtolower($part[5]);
-      $struct->headers['content-transfer-encoding'] = $struct->encoding;
-      }
-    
-    // get part size
-    if (!empty($part[6]) && $part[6]!='NIL')
-      $struct->size = intval($part[6]);
-
-    // read part disposition
-    $di = count($part) - 2;
-    if ((is_array($part[$di]) && count($part[$di]) == 2 && is_array($part[$di][1])) ||
-        (is_array($part[--$di]) && count($part[$di]) == 2))
-      {
-      $struct->disposition = strtolower($part[$di][0]);
-
-      if (is_array($part[$di][1]))
-        for ($n=0; $n<count($part[$di][1]); $n+=2)
-          $struct->d_parameters[strtolower($part[$di][1][$n])] = $part[$di][1][$n+1];
-      }
+            if (isset($struct->ctype_parameters['charset']))
+                $struct->charset = $struct->ctype_parameters['charset'];
+        }
+    
+        // read content encoding
+        if (!empty($part[5]) && $part[5]!='NIL') {
+            $struct->encoding = strtolower($part[5]);
+            $struct->headers['content-transfer-encoding'] = $struct->encoding;
+        }
+    
+        // get part size
+        if (!empty($part[6]) && $part[6]!='NIL')
+            $struct->size = intval($part[6]);
+
+        // read part disposition
+        $di = count($part) - 2;
+        if ((is_array($part[$di]) && count($part[$di]) == 2 && is_array($part[$di][1])) ||
+            (is_array($part[--$di]) && count($part[$di]) == 2)) {
+            $struct->disposition = strtolower($part[$di][0]);
+
+            if (is_array($part[$di][1]))
+                for ($n=0; $n<count($part[$di][1]); $n+=2)
+                    $struct->d_parameters[strtolower($part[$di][1][$n])] = $part[$di][1][$n+1];
+        }
       
-    // get child parts
-    if (is_array($part[8]) && $di != 8)
-      {
-      $struct->parts = array();
-      for ($i=0, $count=0; $i<count($part[8]); $i++)
-        if (is_array($part[8][$i]) && count($part[8][$i]) > 5)
-          $struct->parts[] = $this->_structure_part($part[8][$i], ++$count, $struct->mime_id);
-      }
-
-    // get part ID
-    if (!empty($part[3]) && $part[3]!='NIL')
-      {
-      $struct->content_id = $part[3];
-      $struct->headers['content-id'] = $part[3];
-    
-      if (empty($struct->disposition))
-        $struct->disposition = 'inline';
-      }
-    
-    // fetch message headers if message/rfc822 or named part (could contain Content-Location header)
-    if ($struct->ctype_primary == 'message' || ($struct->ctype_parameters['name'] && !$struct->content_id)) {
-      if (empty($mime_headers))
-        $mime_headers = iil_C_FetchPartHeader($this->conn, $this->mailbox, $this->_msg_id, false, $struct->mime_id);
-      $struct->headers = $this->_parse_headers($mime_headers) + $struct->headers;
-
-      // get real headers for message of type 'message/rfc822'
-      if ($struct->mimetype == 'message/rfc822') {
-        if (empty($raw_headers))
-          $raw_headers = iil_C_FetchMIMEHeaders($this->conn, $this->mailbox, $this->_msg_id, (array)$struct->mime_id, false);
-        $struct->real_headers = $this->_parse_headers($raw_headers);
-
-        // get real content-type of message/rfc822
-        if (preg_match('/^([a-z0-9_\/-]+)/i', $struct->real_headers['content-type'], $matches)) {
-          $struct->real_mimetype = strtolower($matches[1]);
-          }                                                    
-        }
-      }
-
-    if ($struct->ctype_primary=='message') {
-      if (is_array($part[8]) && $di != 8 && empty($struct->parts))
-        $struct->parts[] = $this->_structure_part($part[8], ++$count, $struct->mime_id);
-      }
-
-    // normalize filename property
-    $this->_set_part_filename($struct, $mime_headers);
-
-    return $struct;
-    }
-    
-
-  /**
-   * Set attachment filename from message part structure 
-   *
-   * @access private
-   * @param  object rcube_message_part Part object
-   * @param  string Part's raw headers
-   */
-  private function _set_part_filename(&$part, $headers=null)
-    {
-    if (!empty($part->d_parameters['filename']))
-      $filename_mime = $part->d_parameters['filename'];
-    else if (!empty($part->d_parameters['filename*']))
-      $filename_encoded = $part->d_parameters['filename*'];
-    else if (!empty($part->ctype_parameters['name*']))
-      $filename_encoded = $part->ctype_parameters['name*'];
-    // RFC2231 value continuations
-    // TODO: this should be rewrited to support RFC2231 4.1 combinations
-    else if (!empty($part->d_parameters['filename*0'])) {
-      $i = 0;
-      while (isset($part->d_parameters['filename*'.$i])) {
-        $filename_mime .= $part->d_parameters['filename*'.$i];
-        $i++;
-      }
-      // some servers (eg. dovecot-1.x) have no support for parameter value continuations
-      // we must fetch and parse headers "manually"
-      if ($i<2) {
-        if (!$headers)
-          $headers = iil_C_FetchPartHeader($this->conn, $this->mailbox, $this->_msg_id, false, $part->mime_id);
-        $filename_mime = '';
-        $i = 0;
-        while (preg_match('/filename\*'.$i.'\s*=\s*"*([^"\n;]+)[";]*/', $headers, $matches)) {
-          $filename_mime .= $matches[1];
-          $i++;
-        }
-      }
-    }
-    else if (!empty($part->d_parameters['filename*0*'])) {
-      $i = 0;
-      while (isset($part->d_parameters['filename*'.$i.'*'])) {
-        $filename_encoded .= $part->d_parameters['filename*'.$i.'*'];
-        $i++;
-      }
-      if ($i<2) {
-        if (!$headers)
-          $headers = iil_C_FetchPartHeader($this->conn, $this->mailbox, $this->_msg_id, false, $part->mime_id);
-        $filename_encoded = '';
-        $i = 0; $matches = array();
-        while (preg_match('/filename\*'.$i.'\*\s*=\s*"*([^"\n;]+)[";]*/', $headers, $matches)) {
-          $filename_encoded .= $matches[1];
-          $i++;
-        }
-      }
-    }
-    else if (!empty($part->ctype_parameters['name*0'])) {
-      $i = 0;
-      while (isset($part->ctype_parameters['name*'.$i])) {
-        $filename_mime .= $part->ctype_parameters['name*'.$i];
-        $i++;
-      }
-      if ($i<2) {
-        if (!$headers)
-          $headers = iil_C_FetchPartHeader($this->conn, $this->mailbox, $this->_msg_id, false, $part->mime_id);
-        $filename_mime = '';
-        $i = 0; $matches = array();
-        while (preg_match('/\s+name\*'.$i.'\s*=\s*"*([^"\n;]+)[";]*/', $headers, $matches)) {
-          $filename_mime .= $matches[1];
-          $i++;
-        }
-      }
-    }
-    else if (!empty($part->ctype_parameters['name*0*'])) {
-      $i = 0;
-      while (isset($part->ctype_parameters['name*'.$i.'*'])) {
-        $filename_encoded .= $part->ctype_parameters['name*'.$i.'*'];
-        $i++;
-      }
-      if ($i<2) {
-        if (!$headers)
-          $headers = iil_C_FetchPartHeader($this->conn, $this->mailbox, $this->_msg_id, false, $part->mime_id);
-        $filename_encoded = '';
-        $i = 0; $matches = array();
-        while (preg_match('/\s+name\*'.$i.'\*\s*=\s*"*([^"\n;]+)[";]*/', $headers, $matches)) {
-          $filename_encoded .= $matches[1];
-          $i++;
-        }
-      }
-    }
-    // read 'name' after rfc2231 parameters as it may contains truncated filename (from Thunderbird)
-    else if (!empty($part->ctype_parameters['name']))
-      $filename_mime = $part->ctype_parameters['name'];
-    // Content-Disposition
-    else if (!empty($part->headers['content-description']))
-      $filename_mime = $part->headers['content-description'];
-    else
-      return;
-
-    // decode filename
-    if (!empty($filename_mime)) {
-      $part->filename = rcube_imap::decode_mime_string($filename_mime, 
-        $part->charset ? $part->charset : ($this->struct_charset ? $this->struct_charset :
-          rc_detect_encoding($filename_mime, $this->default_charset)));
-      } 
-    else if (!empty($filename_encoded)) {
-      // decode filename according to RFC 2231, Section 4
-      if (preg_match("/^([^']*)'[^']*'(.*)$/", $filename_encoded, $fmatches)) {
-        $filename_charset = $fmatches[1];
-        $filename_encoded = $fmatches[2];
-        }
-      $part->filename = rcube_charset_convert(urldecode($filename_encoded), $filename_charset);
-      }
-    }
-
-
-  /**
-   * Get charset name from message structure (first part)
-   *
-   * @access private
-   * @param  array  Message structure
-   * @return string Charset name
-   */
-  function _structure_charset($structure)
-    {
-      while (is_array($structure)) {
-        if (is_array($structure[2]) && $structure[2][0] == 'charset')
-          return $structure[2][1];
-        $structure = $structure[0];
-      }
-    } 
+        // get child parts
+        if (is_array($part[8]) && $di != 8) {
+            $struct->parts = array();
+            for ($i=0, $count=0; $i<count($part[8]); $i++)
+                if (is_array($part[8][$i]) && count($part[8][$i]) > 5)
+                    $struct->parts[] = $this->_structure_part($part[8][$i], ++$count, $struct->mime_id);
+        }
 
+        // get part ID
+        if (!empty($part[3]) && $part[3]!='NIL') {
+            $struct->content_id = $part[3];
+            $struct->headers['content-id'] = $part[3];
+    
+            if (empty($struct->disposition))
+                $struct->disposition = 'inline';
+        }
+    
+        // fetch message headers if message/rfc822 or named part (could contain Content-Location header)
+        if ($struct->ctype_primary == 'message' || ($struct->ctype_parameters['name'] && !$struct->content_id)) {
+            if (empty($mime_headers)) {
+                $mime_headers = $this->conn->fetchPartHeader(
+                    $this->mailbox, $this->_msg_id, false, $struct->mime_id);
+            }
+            $struct->headers = $this->_parse_headers($mime_headers) + $struct->headers;
+
+            // get real headers for message of type 'message/rfc822'
+            if ($struct->mimetype == 'message/rfc822') {
+                if (empty($raw_headers)) {
+                    $raw_headers = $this->conn->fetchMIMEHeaders(
+                        $this->mailbox, $this->_msg_id, (array)$struct->mime_id, false);
+                }
+                $struct->real_headers = $this->_parse_headers($raw_headers);
+
+                // get real content-type of message/rfc822
+                if (preg_match('/^([a-z0-9_\/-]+)/i', $struct->real_headers['content-type'], $matches)) {
+                    $struct->real_mimetype = strtolower($matches[1]);
+                }                                                    
+            }
+        }
+
+        if ($struct->ctype_primary=='message') {
+            if (is_array($part[8]) && $di != 8 && empty($struct->parts))
+                $struct->parts[] = $this->_structure_part($part[8], ++$count, $struct->mime_id);
+        }
+
+        // normalize filename property
+        $this->_set_part_filename($struct, $mime_headers);
+
+        return $struct;
+    }
+    
+
+    /**
+     * Set attachment filename from message part structure 
+     *
+     * @access private
+     * @param  object rcube_message_part Part object
+     * @param  string Part's raw headers
+     */
+    private function _set_part_filename(&$part, $headers=null)
+    {
+        if (!empty($part->d_parameters['filename']))
+            $filename_mime = $part->d_parameters['filename'];
+        else if (!empty($part->d_parameters['filename*']))
+            $filename_encoded = $part->d_parameters['filename*'];
+        else if (!empty($part->ctype_parameters['name*']))
+            $filename_encoded = $part->ctype_parameters['name*'];
+        // RFC2231 value continuations
+        // TODO: this should be rewrited to support RFC2231 4.1 combinations
+        else if (!empty($part->d_parameters['filename*0'])) {
+            $i = 0;
+            while (isset($part->d_parameters['filename*'.$i])) {
+                $filename_mime .= $part->d_parameters['filename*'.$i];
+                $i++;
+            }
+            // some servers (eg. dovecot-1.x) have no support for parameter value continuations
+            // we must fetch and parse headers "manually"
+            if ($i<2) {
+                if (!$headers) {
+                    $headers = $this->conn->fetchPartHeader(
+                        $this->mailbox, $this->_msg_id, false, $part->mime_id);
+                }
+                $filename_mime = '';
+                $i = 0;
+                while (preg_match('/filename\*'.$i.'\s*=\s*"*([^"\n;]+)[";]*/', $headers, $matches)) {
+                    $filename_mime .= $matches[1];
+                    $i++;
+                }
+            }
+        }
+        else if (!empty($part->d_parameters['filename*0*'])) {
+            $i = 0;
+            while (isset($part->d_parameters['filename*'.$i.'*'])) {
+                $filename_encoded .= $part->d_parameters['filename*'.$i.'*'];
+                $i++;
+            }
+            if ($i<2) {
+                if (!$headers) {
+                    $headers = $this->conn->fetchPartHeader(
+                            $this->mailbox, $this->_msg_id, false, $part->mime_id);
+                }
+                $filename_encoded = '';
+                $i = 0; $matches = array();
+                while (preg_match('/filename\*'.$i.'\*\s*=\s*"*([^"\n;]+)[";]*/', $headers, $matches)) {
+                    $filename_encoded .= $matches[1];
+                    $i++;
+                }
+            }
+        }
+        else if (!empty($part->ctype_parameters['name*0'])) {
+            $i = 0;
+            while (isset($part->ctype_parameters['name*'.$i])) {
+                $filename_mime .= $part->ctype_parameters['name*'.$i];
+                $i++;
+            }
+            if ($i<2) {
+                if (!$headers) {
+                    $headers = $this->conn->fetchPartHeader(
+                        $this->mailbox, $this->_msg_id, false, $part->mime_id);
+                }
+                $filename_mime = '';
+                $i = 0; $matches = array();
+                while (preg_match('/\s+name\*'.$i.'\s*=\s*"*([^"\n;]+)[";]*/', $headers, $matches)) {
+                    $filename_mime .= $matches[1];
+                    $i++;
+                }
+            }
+        }
+        else if (!empty($part->ctype_parameters['name*0*'])) {
+            $i = 0;
+            while (isset($part->ctype_parameters['name*'.$i.'*'])) {
+                $filename_encoded .= $part->ctype_parameters['name*'.$i.'*'];
+                $i++;
+            }
+            if ($i<2) {
+                if (!$headers) {
+                    $headers = $this->conn->fetchPartHeader(
+                        $this->mailbox, $this->_msg_id, false, $part->mime_id);
+                }
+                $filename_encoded = '';
+                $i = 0; $matches = array();
+                while (preg_match('/\s+name\*'.$i.'\*\s*=\s*"*([^"\n;]+)[";]*/', $headers, $matches)) {
+                    $filename_encoded .= $matches[1];
+                    $i++;
+                }
+            }
+        }
+        // read 'name' after rfc2231 parameters as it may contains truncated filename (from Thunderbird)
+        else if (!empty($part->ctype_parameters['name']))
+            $filename_mime = $part->ctype_parameters['name'];
+        // Content-Disposition
+        else if (!empty($part->headers['content-description']))
+            $filename_mime = $part->headers['content-description'];
+        else
+            return;
+
+        // decode filename
+        if (!empty($filename_mime)) {
+            $part->filename = rcube_imap::decode_mime_string($filename_mime, 
+                $part->charset ? $part->charset : ($this->struct_charset ? $this->struct_charset :
+                rc_detect_encoding($filename_mime, $this->default_charset)));
+        } 
+        else if (!empty($filename_encoded)) {
+            // decode filename according to RFC 2231, Section 4
+            if (preg_match("/^([^']*)'[^']*'(.*)$/", $filename_encoded, $fmatches)) {
+                $filename_charset = $fmatches[1];
+                $filename_encoded = $fmatches[2];
+            }
+            $part->filename = rcube_charset_convert(urldecode($filename_encoded), $filename_charset);
+        }
+    }
+
+
+    /**
+     * Get charset name from message structure (first part)
+     *
+     * @access private
+     * @param  array  Message structure
+     * @return string Charset name
+     */
+    function _structure_charset($structure)
+    {
+        while (is_array($structure)) {
+            if (is_array($structure[2]) && $structure[2][0] == 'charset')
+                return $structure[2][1];
+            $structure = $structure[0];
+        }
+    } 
 
-  /**
-   * Fetch message body of a specific message from the server
-   *
-   * @param  int    Message UID
-   * @param  string Part number
-   * @param  object rcube_message_part Part object created by get_structure()
-   * @param  mixed  True to print part, ressource to write part contents in
-   * @param  resource File pointer to save the message part
-   * @return string Message/part body if not printed
-   */
-  function &get_message_part($uid, $part=1, $o_part=NULL, $print=NULL, $fp=NULL)
-    {
-    // get part encoding if not provided
-    if (!is_object($o_part))
-      {
-      $structure_str = iil_C_FetchStructureString($this->conn, $this->mailbox, $uid, true); 
-      $structure = iml_GetRawStructureArray($structure_str);
-      // error or message not found
-      if (empty($structure))
-        return false;
 
-      $part_type = iml_GetPartTypeCode($structure, $part);
-      $o_part = new rcube_message_part;
-      $o_part->ctype_primary = $part_type==0 ? 'text' : ($part_type==2 ? 'message' : 'other');
-      $o_part->encoding = strtolower(iml_GetPartEncodingString($structure, $part));
-      $o_part->charset = iml_GetPartCharset($structure, $part);
-      }
+    /**
+     * Fetch message body of a specific message from the server
+     *
+     * @param  int    Message UID
+     * @param  string Part number
+     * @param  object rcube_message_part Part object created by get_structure()
+     * @param  mixed  True to print part, ressource to write part contents in
+     * @param  resource File pointer to save the message part
+     * @return string Message/part body if not printed
+     */
+    function &get_message_part($uid, $part=1, $o_part=NULL, $print=NULL, $fp=NULL)
+    {
+        // get part encoding if not provided
+        if (!is_object($o_part)) {
+            $structure_str = $this->conn->fetchStructureString($this->mailbox, $uid, true); 
+            $structure = iml_GetRawStructureArray($structure_str);
+            // error or message not found
+            if (empty($structure))
+                return false;
+
+            $part_type = iml_GetPartTypeCode($structure, $part);
+            $o_part = new rcube_message_part;
+            $o_part->ctype_primary = $part_type==0 ? 'text' : ($part_type==2 ? 'message' : 'other');
+            $o_part->encoding = strtolower(iml_GetPartEncodingString($structure, $part));
+            $o_part->charset = iml_GetPartCharset($structure, $part);
+        }
       
-    // TODO: Add caching for message parts
+        // TODO: Add caching for message parts
 
-    if (!$part) $part = 'TEXT';
+        if (!$part) $part = 'TEXT';
 
-    $body = iil_C_HandlePartBody($this->conn, $this->mailbox, $uid, true, $part,
-        $o_part->encoding, $print, $fp);
+        $body = $this->conn->handlePartBody($this->mailbox, $uid, true, $part,
+            $o_part->encoding, $print, $fp);
 
-    if ($fp || $print)
-      return true;
+        if ($fp || $print)
+            return true;
 
-    // convert charset (if text or message part)
-    if ($o_part->ctype_primary=='text' || $o_part->ctype_primary=='message') {
-      // assume default if no charset specified
-      if (empty($o_part->charset) || strtolower($o_part->charset) == 'us-ascii')
-        $o_part->charset = $this->default_charset;
+        // convert charset (if text or message part)
+        if ($o_part->ctype_primary=='text' || $o_part->ctype_primary=='message') {
+            // assume default if no charset specified
+            if (empty($o_part->charset) || strtolower($o_part->charset) == 'us-ascii')
+                $o_part->charset = $this->default_charset;
 
-      $body = rcube_charset_convert($body, $o_part->charset);
-      }
+            $body = rcube_charset_convert($body, $o_part->charset);
+        }
     
-    return $body;
+        return $body;
     }
 
 
-  /**
-   * Fetch message body of a specific message from the server
-   *
-   * @param  int    Message UID
-   * @return string Message/part body
-   * @see    rcube_imap::get_message_part()
-   */
-  function &get_body($uid, $part=1)
+    /**
+     * Fetch message body of a specific message from the server
+     *
+     * @param  int    Message UID
+     * @return string Message/part body
+     * @see    rcube_imap::get_message_part()
+     */
+    function &get_body($uid, $part=1)
     {
-    $headers = $this->get_headers($uid);
-    return rcube_charset_convert($this->get_message_part($uid, $part, NULL),
-      $headers->charset ? $headers->charset : $this->default_charset);
+        $headers = $this->get_headers($uid);
+        return rcube_charset_convert($this->get_message_part($uid, $part, NULL),
+            $headers->charset ? $headers->charset : $this->default_charset);
     }
 
 
-  /**
-   * Returns the whole message source as string
-   *
-   * @param int  Message UID
-   * @return string Message source string
-   */
-  function &get_raw_body($uid)
+    /**
+     * Returns the whole message source as string
+     *
+     * @param int  Message UID
+     * @return string Message source string
+     */
+    function &get_raw_body($uid)
     {
-    return iil_C_HandlePartBody($this->conn, $this->mailbox, $uid, true);
+        return $this->conn->handlePartBody($this->mailbox, $uid, true);
     }
 
 
-  /**
-   * Returns the message headers as string
-   *
-   * @param int  Message UID
-   * @return string Message headers string
-   */
-  function &get_raw_headers($uid)
+    /**
+     * Returns the message headers as string
+     *
+     * @param int  Message UID
+     * @return string Message headers string
+     */
+    function &get_raw_headers($uid)
     {
-    return iil_C_FetchPartHeader($this->conn, $this->mailbox, $uid, true);
+        return $this->conn->fetchPartHeader($this->mailbox, $uid, true);
     }
     
 
-  /**
-   * Sends the whole message source to stdout
-   *
-   * @param int  Message UID
-   */ 
-  function print_raw_body($uid)
+    /**
+     * Sends the whole message source to stdout
+     *
+     * @param int  Message UID
+     */ 
+    function print_raw_body($uid)
     {
-    iil_C_HandlePartBody($this->conn, $this->mailbox, $uid, true, NULL, NULL, true);
+        $this->conn->handlePartBody($this->mailbox, $uid, true, NULL, NULL, true);
     }
 
 
-  /**
-   * Set message flag to one or several messages
-   *
-   * @param mixed   Message UIDs as array or comma-separated string, or '*'
-   * @param string  Flag to set: SEEN, UNDELETED, DELETED, RECENT, ANSWERED, DRAFT, MDNSENT
-   * @param string  Folder name
-   * @param boolean True to skip message cache clean up
-   * @return int    Number of flagged messages, -1 on failure
-   */
-  function set_flag($uids, $flag, $mbox_name=NULL, $skip_cache=false)
+    /**
+     * Set message flag to one or several messages
+     *
+     * @param mixed   Message UIDs as array or comma-separated string, or '*'
+     * @param string  Flag to set: SEEN, UNDELETED, DELETED, RECENT, ANSWERED, DRAFT, MDNSENT
+     * @param string  Folder name
+     * @param boolean True to skip message cache clean up
+     * @return int    Number of flagged messages, -1 on failure
+     */
+    function set_flag($uids, $flag, $mbox_name=NULL, $skip_cache=false)
     {
-    $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
-
-    $flag = strtoupper($flag);
-    list($uids, $all_mode) = $this->_parse_uids($uids, $mailbox);
+        $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
 
-    if (strpos($flag, 'UN') === 0)
-      $result = iil_C_UnFlag($this->conn, $mailbox, $uids, substr($flag, 2));
-    else
-      $result = iil_C_Flag($this->conn, $mailbox, $uids, $flag);
+        $flag = strtoupper($flag);
+        list($uids, $all_mode) = $this->_parse_uids($uids, $mailbox);
 
-    if ($result >= 0) {
-      // reload message headers if cached
-      if ($this->caching_enabled && !$skip_cache) {
-        $cache_key = $mailbox.'.msg';
-        if ($all_mode)
-          $this->clear_message_cache($cache_key);
+        if (strpos($flag, 'UN') === 0)
+            $result = $this->conn->unflag($mailbox, $uids, substr($flag, 2));
         else
-          $this->remove_message_cache($cache_key, explode(',', $uids));
-        }
-      // update counters
-      if ($flag=='SEEN')
-        $this->_set_messagecount($mailbox, 'UNSEEN', $result*(-1));
-      else if ($flag=='UNSEEN')
-        $this->_set_messagecount($mailbox, 'UNSEEN', $result);
-      else if ($flag=='DELETED')
-        $this->_set_messagecount($mailbox, 'ALL', $result*(-1));
-      }
-
-    return $result;
-    }
-
-
-  /**
-   * Remove message flag for one or several messages
-   *
-   * @param mixed  Message UIDs as array or comma-separated string, or '*'
-   * @param string Flag to unset: SEEN, DELETED, RECENT, ANSWERED, DRAFT, MDNSENT
-   * @param string Folder name
-   * @return int   Number of flagged messages, -1 on failure
-   * @see set_flag
-   */
-  function unset_flag($uids, $flag, $mbox_name=NULL)
-    {
-    return $this->set_flag($uids, 'UN'.$flag, $mbox_name);
-    }
-
-
-  /**
-   * Append a mail message (source) to a specific mailbox
-   *
-   * @param string   Target mailbox
-   * @param string   The message source string or filename
-   * @param string   Headers string if $message contains only the body
-   * @param boolean  True if $message is a filename
-   *
-   * @return boolean True on success, False on error
-   */
-  function save_message($mbox_name, &$message, $headers='', $is_file=false)
-    {
-    $mailbox = $this->mod_mailbox($mbox_name);
-
-    // make sure mailbox exists
-    if ($this->mailbox_exists($mbox_name, true)) {
-      if ($is_file) {
-        $separator = rcmail::get_instance()->config->header_delimiter();
-        $saved = iil_C_AppendFromFile($this->conn, $mailbox, $message,
-          $headers, $separator.$separator);
-        }
-      else
-        $saved = iil_C_Append($this->conn, $mailbox, $message);
-      }
-
-    if ($saved)
-      {
-      // increase messagecount of the target mailbox
-      $this->_set_messagecount($mailbox, 'ALL', 1);
-      }
-
-    return $saved;
-    }
-
-
-  /**
-   * Move a message from one mailbox to another
-   *
-   * @param mixed  Message UIDs as array or comma-separated string, or '*'
-   * @param string Target mailbox
-   * @param string Source mailbox
-   * @return boolean True on success, False on error
-   */
-  function move_message($uids, $to_mbox, $from_mbox='')
-  {
-    $fbox = $from_mbox;
-    $tbox = $to_mbox;
-    $to_mbox = $this->mod_mailbox($to_mbox);
-    $from_mbox = $from_mbox ? $this->mod_mailbox($from_mbox) : $this->mailbox;
-
-    list($uids, $all_mode) = $this->_parse_uids($uids, $from_mbox);
-
-    // exit if no message uids are specified
-    if (empty($uids))
-      return false;
-
-    // make sure mailbox exists
-    if ($to_mbox != 'INBOX' && !$this->mailbox_exists($tbox, true))
-      {
-      if (in_array($tbox, $this->default_folders))
-        $this->create_mailbox($tbox, true);
-      else
-        return false;
-      }
-
-    // flag messages as read before moving them
-    $config = rcmail::get_instance()->config;
-    if ($config->get('read_when_deleted') && $tbox == $config->get('trash_mbox')) {
-      // don't flush cache (4th argument)
-      $this->set_flag($uids, 'SEEN', $fbox, true);
-      }
-
-    // move messages
-    $iil_move = iil_C_Move($this->conn, $uids, $from_mbox, $to_mbox);
-    $moved = !($iil_move === false || $iil_move < 0);
-
-    // send expunge command in order to have the moved message
-    // really deleted from the source mailbox
-    if ($moved) {
-      $this->_expunge($from_mbox, false, $uids);
-      $this->_clear_messagecount($from_mbox);
-      $this->_clear_messagecount($to_mbox);
-    }
-    // moving failed
-    else if ($config->get('delete_always', false) && $tbox == $config->get('trash_mbox')) {
-      $moved = $this->delete_message($uids, $fbox);
-    }
-
-    if ($moved) {
-      // unset threads internal cache
-      unset($this->icache['threads']);
-
-      // remove message ids from search set
-      if ($this->search_set && $from_mbox == $this->mailbox) {
-        // threads are too complicated to just remove messages from set
-        if ($this->search_threads || $all_mode)
-          $this->refresh_search();
-        else {
-          $uids = explode(',', $uids);
-          foreach ($uids as $uid)
-            $a_mids[] = $this->_uid2id($uid, $from_mbox);
-          $this->search_set = array_diff($this->search_set, $a_mids);
-          }
+            $result = $this->conn->flag($mailbox, $uids, $flag);
+
+        if ($result >= 0) {
+            // reload message headers if cached
+            if ($this->caching_enabled && !$skip_cache) {
+                $cache_key = $mailbox.'.msg';
+                if ($all_mode)
+                    $this->clear_message_cache($cache_key);
+                else
+                    $this->remove_message_cache($cache_key, explode(',', $uids));
+            }
+            // update counters
+            if ($flag=='SEEN')
+                $this->_set_messagecount($mailbox, 'UNSEEN', $result*(-1));
+            else if ($flag=='UNSEEN')
+                $this->_set_messagecount($mailbox, 'UNSEEN', $result);
+            else if ($flag=='DELETED')
+                $this->_set_messagecount($mailbox, 'ALL', $result*(-1));
         }
 
-      // update cached message headers
-      $cache_key = $from_mbox.'.msg';
-      if ($all_mode || ($start_index = $this->get_message_cache_index_min($cache_key, $uids))) {
-        // clear cache from the lowest index on
-        $this->clear_message_cache($cache_key, $all_mode ? 1 : $start_index);
-       }
-    }
-
-    return $moved;
-  }
-
-
-  /**
-   * Copy a message from one mailbox to another
-   *
-   * @param mixed  Message UIDs as array or comma-separated string, or '*'
-   * @param string Target mailbox
-   * @param string Source mailbox
-   * @return boolean True on success, False on error
-   */
-  function copy_message($uids, $to_mbox, $from_mbox='')
-  {
-    $fbox = $from_mbox;
-    $tbox = $to_mbox;
-    $to_mbox = $this->mod_mailbox($to_mbox);
-    $from_mbox = $from_mbox ? $this->mod_mailbox($from_mbox) : $this->mailbox;
-
-    list($uids, $all_mode) = $this->_parse_uids($uids, $from_mbox);
-
-    // exit if no message uids are specified
-    if (empty($uids))
-      return false;
-
-    // make sure mailbox exists
-    if ($to_mbox != 'INBOX' && !$this->mailbox_exists($tbox, true))
-      {
-      if (in_array($tbox, $this->default_folders))
-        $this->create_mailbox($tbox, true);
-      else
-        return false;
-      }
+        return $result;
+    }
 
-    // copy messages
-    $iil_copy = iil_C_Copy($this->conn, $uids, $from_mbox, $to_mbox);
-    $copied = !($iil_copy === false || $iil_copy < 0);
 
-    if ($copied) {
-      $this->_clear_messagecount($to_mbox);
+    /**
+     * Remove message flag for one or several messages
+     *
+     * @param mixed  Message UIDs as array or comma-separated string, or '*'
+     * @param string Flag to unset: SEEN, DELETED, RECENT, ANSWERED, DRAFT, MDNSENT
+     * @param string Folder name
+     * @return int   Number of flagged messages, -1 on failure
+     * @see set_flag
+     */
+    function unset_flag($uids, $flag, $mbox_name=NULL)
+    {
+        return $this->set_flag($uids, 'UN'.$flag, $mbox_name);
     }
 
-    return $copied;
-  }
 
+    /**
+     * Append a mail message (source) to a specific mailbox
+     *
+     * @param string   Target mailbox
+     * @param string   The message source string or filename
+     * @param string   Headers string if $message contains only the body
+     * @param boolean  True if $message is a filename
+     *
+     * @return boolean True on success, False on error
+     */
+    function save_message($mbox_name, &$message, $headers='', $is_file=false)
+    {
+        $mailbox = $this->mod_mailbox($mbox_name);
 
-  /**
-   * Mark messages as deleted and expunge mailbox
-   *
-   * @param mixed  Message UIDs as array or comma-separated string, or '*'
-   * @param string Source mailbox
-   * @return boolean True on success, False on error
-   */
-  function delete_message($uids, $mbox_name='')
-  {
-    $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
+        // make sure mailbox exists
+        if ($this->mailbox_exists($mbox_name, true)) {
+            if ($is_file) {
+                $separator = rcmail::get_instance()->config->header_delimiter();
+                $saved = $this->conn->appendFromFile($mailbox, $message,
+                    $headers, $separator.$separator);
+            }
+            else
+                $saved = $this->conn->append($mailbox, $message);
+        }
 
-    list($uids, $all_mode) = $this->_parse_uids($uids, $mailbox);
+        if ($saved) {
+            // increase messagecount of the target mailbox
+            $this->_set_messagecount($mailbox, 'ALL', 1);
+        }
 
-    // exit if no message uids are specified
-    if (empty($uids))
-      return false;
+        return $saved;
+    }
 
-    $deleted = iil_C_Delete($this->conn, $mailbox, $uids);
 
-    if ($deleted) {
-      // send expunge command in order to have the deleted message
-      // really deleted from the mailbox
-      $this->_expunge($mailbox, false, $uids);
-      $this->_clear_messagecount($mailbox);
-      unset($this->uid_id_map[$mailbox]);
+    /**
+     * Move a message from one mailbox to another
+     *
+     * @param mixed  Message UIDs as array or comma-separated string, or '*'
+     * @param string Target mailbox
+     * @param string Source mailbox
+     * @return boolean True on success, False on error
+     */
+    function move_message($uids, $to_mbox, $from_mbox='')
+    {
+        $fbox = $from_mbox;
+        $tbox = $to_mbox;
+        $to_mbox = $this->mod_mailbox($to_mbox);
+        $from_mbox = $from_mbox ? $this->mod_mailbox($from_mbox) : $this->mailbox;
 
-      // unset threads internal cache
-      unset($this->icache['threads']);
-      
-      // remove message ids from search set
-      if ($this->search_set && $mailbox == $this->mailbox) {
-        // threads are too complicated to just remove messages from set
-        if ($this->search_threads || $all_mode)
-          $this->refresh_search();
-        else {
-          $uids = explode(',', $uids);
-          foreach ($uids as $uid)
-            $a_mids[] = $this->_uid2id($uid, $mailbox);
-          $this->search_set = array_diff($this->search_set, $a_mids);
-          }
+        list($uids, $all_mode) = $this->_parse_uids($uids, $from_mbox);
+
+        // exit if no message uids are specified
+        if (empty($uids))
+            return false;
+
+        // make sure mailbox exists
+        if ($to_mbox != 'INBOX' && !$this->mailbox_exists($tbox, true)) {
+            if (in_array($tbox, $this->default_folders))
+                $this->create_mailbox($tbox, true);
+            else
+                return false;
+        }
+
+        // flag messages as read before moving them
+        $config = rcmail::get_instance()->config;
+        if ($config->get('read_when_deleted') && $tbox == $config->get('trash_mbox')) {
+            // don't flush cache (4th argument)
+            $this->set_flag($uids, 'SEEN', $fbox, true);
+        }
+
+        // move messages
+        $move = $this->conn->move($uids, $from_mbox, $to_mbox);
+        $moved = !($move === false || $move < 0);
+
+        // send expunge command in order to have the moved message
+        // really deleted from the source mailbox
+        if ($moved) {
+            $this->_expunge($from_mbox, false, $uids);
+            $this->_clear_messagecount($from_mbox);
+            $this->_clear_messagecount($to_mbox);
+        }
+        // moving failed
+        else if ($config->get('delete_always', false) && $tbox == $config->get('trash_mbox')) {
+            $moved = $this->delete_message($uids, $fbox);
         }
 
-      // remove deleted messages from cache
-      $cache_key = $mailbox.'.msg';
-      if ($all_mode || ($start_index = $this->get_message_cache_index_min($cache_key, $uids))) {
-        // clear cache from the lowest index on
-        $this->clear_message_cache($cache_key, $all_mode ? 1 : $start_index);
-      }
+        if ($moved) {
+            // unset threads internal cache
+            unset($this->icache['threads']);
+
+            // remove message ids from search set
+            if ($this->search_set && $from_mbox == $this->mailbox) {
+                // threads are too complicated to just remove messages from set
+                if ($this->search_threads || $all_mode)
+                    $this->refresh_search();
+                else {
+                    $uids = explode(',', $uids);
+                    foreach ($uids as $uid)
+                        $a_mids[] = $this->_uid2id($uid, $from_mbox);
+                    $this->search_set = array_diff($this->search_set, $a_mids);
+                }
+            }
+
+            // update cached message headers
+            $cache_key = $from_mbox.'.msg';
+            if ($all_mode || ($start_index = $this->get_message_cache_index_min($cache_key, $uids))) {
+                // clear cache from the lowest index on
+                $this->clear_message_cache($cache_key, $all_mode ? 1 : $start_index);
+            }
+        }
+
+        return $moved;
     }
 
-    return $deleted;
-  }
 
+    /**
+     * Copy a message from one mailbox to another
+     *
+     * @param mixed  Message UIDs as array or comma-separated string, or '*'
+     * @param string Target mailbox
+     * @param string Source mailbox
+     * @return boolean True on success, False on error
+     */
+    function copy_message($uids, $to_mbox, $from_mbox='')
+    {
+        $fbox = $from_mbox;
+        $tbox = $to_mbox;
+        $to_mbox = $this->mod_mailbox($to_mbox);
+        $from_mbox = $from_mbox ? $this->mod_mailbox($from_mbox) : $this->mailbox;
 
-  /**
-   * Clear all messages in a specific mailbox
-   *
-   * @param string Mailbox name
-   * @return int Above 0 on success
-   */
-  function clear_mailbox($mbox_name=NULL)
+        list($uids, $all_mode) = $this->_parse_uids($uids, $from_mbox);
+
+        // exit if no message uids are specified
+        if (empty($uids))
+            return false;
+
+        // make sure mailbox exists
+        if ($to_mbox != 'INBOX' && !$this->mailbox_exists($tbox, true)) {
+            if (in_array($tbox, $this->default_folders))
+                $this->create_mailbox($tbox, true);
+            else
+                return false;
+        }
+
+        // copy messages
+        $copy = $this->conn->copy($uids, $from_mbox, $to_mbox);
+        $copied = !($copy === false || $copy < 0);
+
+        if ($copied) {
+            $this->_clear_messagecount($to_mbox);
+        }
+
+        return $copied;
+    }
+
+
+    /**
+     * Mark messages as deleted and expunge mailbox
+     *
+     * @param mixed  Message UIDs as array or comma-separated string, or '*'
+     * @param string Source mailbox
+     * @return boolean True on success, False on error
+     */
+    function delete_message($uids, $mbox_name='')
     {
-    $mailbox = !empty($mbox_name) ? $this->mod_mailbox($mbox_name) : $this->mailbox;
-    $msg_count = $this->_messagecount($mailbox, 'ALL');
-    
-    if ($msg_count>0)
-      {
-      $cleared = iil_C_ClearFolder($this->conn, $mailbox);
+        $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
+
+        list($uids, $all_mode) = $this->_parse_uids($uids, $mailbox);
+
+        // exit if no message uids are specified
+        if (empty($uids))
+            return false;
+
+        $deleted = $this->conn->delete($mailbox, $uids);
+
+        if ($deleted) {
+            // send expunge command in order to have the deleted message
+            // really deleted from the mailbox
+            $this->_expunge($mailbox, false, $uids);
+            $this->_clear_messagecount($mailbox);
+            unset($this->uid_id_map[$mailbox]);
+
+            // unset threads internal cache
+            unset($this->icache['threads']);
       
-      // make sure the message count cache is cleared as well
-      if ($cleared)
-        {
-        $this->clear_message_cache($mailbox.'.msg');      
-        $a_mailbox_cache = $this->get_cache('messagecount');
-        unset($a_mailbox_cache[$mailbox]);
-        $this->update_cache('messagecount', $a_mailbox_cache);
+            // remove message ids from search set
+            if ($this->search_set && $mailbox == $this->mailbox) {
+                // threads are too complicated to just remove messages from set
+                if ($this->search_threads || $all_mode)
+                    $this->refresh_search();
+                else {
+                    $uids = explode(',', $uids);
+                    foreach ($uids as $uid)
+                        $a_mids[] = $this->_uid2id($uid, $mailbox);
+                    $this->search_set = array_diff($this->search_set, $a_mids);
+                }
+            }
+
+            // remove deleted messages from cache
+            $cache_key = $mailbox.'.msg';
+            if ($all_mode || ($start_index = $this->get_message_cache_index_min($cache_key, $uids))) {
+                // clear cache from the lowest index on
+                $this->clear_message_cache($cache_key, $all_mode ? 1 : $start_index);
+            }
+        }
+
+        return $deleted;
+    }
+
+
+    /**
+     * Clear all messages in a specific mailbox
+     *
+     * @param string Mailbox name
+     * @return int Above 0 on success
+     */
+    function clear_mailbox($mbox_name=NULL)
+    {
+        $mailbox = !empty($mbox_name) ? $this->mod_mailbox($mbox_name) : $this->mailbox;
+        $msg_count = $this->_messagecount($mailbox, 'ALL');
+    
+        if (!$msg_count) {
+            return 0;
         }
         
-      return $cleared;
-      }
-    else
-      return 0;
-    }
-
-
-  /**
-   * Send IMAP expunge command and clear cache
-   *
-   * @param string Mailbox name
-   * @param boolean False if cache should not be cleared
-   * @return boolean True on success
-   */
-  function expunge($mbox_name='', $clear_cache=true)
-    {
-    $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
-    return $this->_expunge($mailbox, $clear_cache);
-    }
-
-
-  /**
-   * Send IMAP expunge command and clear cache
-   *
-   * @param string 	 Mailbox name
-   * @param boolean  False if cache should not be cleared
-   * @param mixed    Message UIDs as array or comma-separated string, or '*'
-   * @return boolean True on success
-   * @access private
-   * @see rcube_imap::expunge()
-   */
-  private function _expunge($mailbox, $clear_cache=true, $uids=NULL)
-    {
-    if ($uids && $this->get_capability('UIDPLUS')) 
-      $a_uids = is_array($uids) ? join(',', $uids) : $uids;
-    else
-      $a_uids = NULL;
-
-    $result = iil_C_Expunge($this->conn, $mailbox, $a_uids);
-
-    if ($result>=0 && $clear_cache)
-      {
-      $this->clear_message_cache($mailbox.'.msg');
-      $this->_clear_messagecount($mailbox);
-      }
+        $cleared = $this->conn->clearFolder($mailbox);
       
-    return $result;
+        // make sure the message count cache is cleared as well
+        if ($cleared) {
+            $this->clear_message_cache($mailbox.'.msg');      
+            $a_mailbox_cache = $this->get_cache('messagecount');
+            unset($a_mailbox_cache[$mailbox]);
+            $this->update_cache('messagecount', $a_mailbox_cache);
+        }
+        
+        return $cleared;
     }
 
 
-  /**
-   * Parse message UIDs input
-   *
-   * @param mixed  UIDs array or comma-separated list or '*' or '1:*'
-   * @param string Mailbox name
-   * @return array Two elements array with UIDs converted to list and ALL flag 
-   * @access private
-   */
-  private function _parse_uids($uids, $mailbox)
+    /**
+     * Send IMAP expunge command and clear cache
+     *
+     * @param string Mailbox name
+     * @param boolean False if cache should not be cleared
+     * @return boolean True on success
+     */
+    function expunge($mbox_name='', $clear_cache=true)
     {
-    if ($uids === '*' || $uids === '1:*') {
-      if (empty($this->search_set)) {
-        $uids = '1:*';
-        $all = true;
-        }
-      // get UIDs from current search set
-      // @TODO: skip iil_C_FetchUIDs() and work with IDs instead of UIDs (?)
-      else {
-        if ($this->search_threads)
-          $uids = iil_C_FetchUIDs($this->conn, $mailbox, array_keys($this->search_set['depth']));
+        $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
+        return $this->_expunge($mailbox, $clear_cache);
+    }
+
+
+    /**
+     * Send IMAP expunge command and clear cache
+     *
+     * @param string 	 Mailbox name
+     * @param boolean  False if cache should not be cleared
+     * @param mixed    Message UIDs as array or comma-separated string, or '*'
+     * @return boolean True on success
+     * @access private
+     * @see rcube_imap::expunge()
+     */
+    private function _expunge($mailbox, $clear_cache=true, $uids=NULL)
+    {
+        if ($uids && $this->get_capability('UIDPLUS')) 
+            $a_uids = is_array($uids) ? join(',', $uids) : $uids;
         else
-          $uids = iil_C_FetchUIDs($this->conn, $mailbox, $this->search_set);
+            $a_uids = NULL;
+
+        $result = $this->conn->expunge($mailbox, $a_uids);
+
+        if ($result>=0 && $clear_cache) {
+            $this->clear_message_cache($mailbox.'.msg');
+            $this->_clear_messagecount($mailbox);
+        }
+      
+        return $result;
+    }
+
+
+    /**
+     * Parse message UIDs input
+     *
+     * @param mixed  UIDs array or comma-separated list or '*' or '1:*'
+     * @param string Mailbox name
+     * @return array Two elements array with UIDs converted to list and ALL flag 
+     * @access private
+     */
+    private function _parse_uids($uids, $mailbox)
+    {
+        if ($uids === '*' || $uids === '1:*') {
+            if (empty($this->search_set)) {
+                $uids = '1:*';
+                $all = true;
+            }
+            // get UIDs from current search set
+            // @TODO: skip fetchUIDs() and work with IDs instead of UIDs (?)
+            else {
+                if ($this->search_threads)
+                    $uids = $this->conn->fetchUIDs($mailbox, array_keys($this->search_set['depth']));
+                else
+                    $uids = $this->conn->fetchUIDs($mailbox, $this->search_set);
       
-        // save ID-to-UID mapping in local cache
-        if (is_array($uids))
-          foreach ($uids as $id => $uid)
-            $this->uid_id_map[$mailbox][$uid] = $id;
+                // save ID-to-UID mapping in local cache
+                if (is_array($uids))
+                    foreach ($uids as $id => $uid)
+                        $this->uid_id_map[$mailbox][$uid] = $id;
+
+                $uids = join(',', $uids);
+            }
+        }
+        else {
+            if (is_array($uids))
+                $uids = join(',', $uids);
+
+            if (preg_match('/[^0-9,]/', $uids))
+                $uids = '';
+        }
+
+        return array($uids, (bool) $all);
+    }
+
 
-        $uids = join(',', $uids);
+    /**
+     * Translate UID to message ID
+     *
+     * @param int    Message UID
+     * @param string Mailbox name
+     * @return int   Message ID
+     */
+    function get_id($uid, $mbox_name=NULL) 
+    {
+        $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
+        return $this->_uid2id($uid, $mailbox);
+    }
+
+
+    /**
+     * Translate message number to UID
+     *
+     * @param int    Message ID
+     * @param string Mailbox name
+     * @return int   Message UID
+     */
+    function get_uid($id,$mbox_name=NULL)
+    {
+        $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
+        return $this->_id2uid($id, $mailbox);
+    }
+
+
+
+    /* --------------------------------
+     *        folder managment
+     * --------------------------------*/
+
+    /**
+     * Public method for mailbox listing.
+     *
+     * Converts mailbox name with root dir first
+     *
+     * @param   string  Optional root folder
+     * @param   string  Optional filter for mailbox listing
+     * @return  array   List of mailboxes/folders
+     * @access  public
+     */
+    function list_mailboxes($root='', $filter='*')
+    {
+        $a_out = array();
+        $a_mboxes = $this->_list_mailboxes($root, $filter);
+
+        foreach ($a_mboxes as $mbox_row) {
+            $name = $this->mod_mailbox($mbox_row, 'out');
+            if (strlen($name))
+                $a_out[] = $name;
         }
-      }
-    else {
-      if (is_array($uids))
-        $uids = join(',', $uids);
 
-      if (preg_match('/[^0-9,]/', $uids))
-        $uids = '';
-      }
+        // INBOX should always be available
+        if (!in_array('INBOX', $a_out))
+            array_unshift($a_out, 'INBOX');
 
-    return array($uids, (bool) $all);
+        // sort mailboxes
+        $a_out = $this->_sort_mailbox_list($a_out);
+
+        return $a_out;
     }
+
+
+    /**
+     * Private method for mailbox listing
+     *
+     * @return  array   List of mailboxes/folders
+     * @see     rcube_imap::list_mailboxes()
+     * @access  private
+     */
+    private function _list_mailboxes($root='', $filter='*')
+    {
+        $a_defaults = $a_out = array();
     
+        // get cached folder list    
+        $a_mboxes = $this->get_cache('mailboxes');
+        if (is_array($a_mboxes))
+            return $a_mboxes;
+
+        // Give plugins a chance to provide a list of mailboxes
+        $data = rcmail::get_instance()->plugins->exec_hook('list_mailboxes',
+            array('root'=>$root,'filter'=>$filter));
+    
+        if (isset($data['folders'])) {
+            $a_folders = $data['folders'];
+        }
+        else {
+            // retrieve list of folders from IMAP server
+            $a_folders = $this->conn->listSubscribed($this->mod_mailbox($root), $filter);
+        }
+    
+        if (!is_array($a_folders) || !sizeof($a_folders))
+            $a_folders = array();
+
+        // write mailboxlist to cache
+        $this->update_cache('mailboxes', $a_folders);
+    
+        return $a_folders;
+    }
 
-  /* --------------------------------
-   *        folder managment
-   * --------------------------------*/
 
-  /**
-   * Get a list of all folders available on the IMAP server
-   * 
-   * @param string IMAP root dir
-   * @return array Indexed array with folder names
-   */
-  function list_unsubscribed($root='')
+    /**
+     * Get a list of all folders available on the IMAP server
+     * 
+     * @param string IMAP root dir
+     * @return array Indexed array with folder names
+     */
+    function list_unsubscribed($root='')
     {
-    static $sa_unsubscribed;
+        static $sa_unsubscribed;
     
-    if (is_array($sa_unsubscribed))
-      return $sa_unsubscribed;
+        if (is_array($sa_unsubscribed))
+            return $sa_unsubscribed;
       
-    // retrieve list of folders from IMAP server
-    $a_mboxes = iil_C_ListMailboxes($this->conn, $this->mod_mailbox($root), '*');
+        // retrieve list of folders from IMAP server
+        $a_mboxes = $this->conn->listMailboxes($this->mod_mailbox($root), '*');
 
-    // modify names with root dir
-    foreach ($a_mboxes as $mbox_name)
-      {
-      $name = $this->mod_mailbox($mbox_name, 'out');
-      if (strlen($name))
-        $a_folders[] = $name;
-      }
+        // modify names with root dir
+        foreach ($a_mboxes as $mbox_name) {
+            $name = $this->mod_mailbox($mbox_name, 'out');
+            if (strlen($name))
+                $a_folders[] = $name;
+        }
 
-    // filter folders and sort them
-    $sa_unsubscribed = $this->_sort_mailbox_list($a_folders);
-    return $sa_unsubscribed;
+        // filter folders and sort them
+        $sa_unsubscribed = $this->_sort_mailbox_list($a_folders);
+        return $sa_unsubscribed;
     }
 
 
-  /**
-   * Get mailbox quota information
-   * added by Nuny
-   * 
-   * @return mixed Quota info or False if not supported
-   */
-  function get_quota()
+    /**
+     * Get mailbox quota information
+     * added by Nuny
+     * 
+     * @return mixed Quota info or False if not supported
+     */
+    function get_quota()
     {
-    if ($this->get_capability('QUOTA'))
-      return iil_C_GetQuota($this->conn);
+        if ($this->get_capability('QUOTA'))
+            return $this->conn->getQuota();
 	
-    return false;
+        return false;
     }
 
 
-  /**
-   * Subscribe to a specific mailbox(es)
-   *
-   * @param array Mailbox name(s)
-   * @return boolean True on success
-   */ 
-  function subscribe($a_mboxes)
+    /**
+     * Subscribe to a specific mailbox(es)
+     *
+     * @param array Mailbox name(s)
+     * @return boolean True on success
+     */ 
+    function subscribe($a_mboxes)
     {
-    if (!is_array($a_mboxes))
-      $a_mboxes = array($a_mboxes);
+        if (!is_array($a_mboxes))
+            $a_mboxes = array($a_mboxes);
 
-    // let this common function do the main work
-    return $this->_change_subscription($a_mboxes, 'subscribe');
+        // let this common function do the main work
+        return $this->_change_subscription($a_mboxes, 'subscribe');
     }
 
 
-  /**
-   * Unsubscribe mailboxes
-   *
-   * @param array Mailbox name(s)
-   * @return boolean True on success
-   */
-  function unsubscribe($a_mboxes)
+    /**
+     * Unsubscribe mailboxes
+     *
+     * @param array Mailbox name(s)
+     * @return boolean True on success
+     */
+    function unsubscribe($a_mboxes)
     {
-    if (!is_array($a_mboxes))
-      $a_mboxes = array($a_mboxes);
+        if (!is_array($a_mboxes))
+            $a_mboxes = array($a_mboxes);
 
-    // let this common function do the main work
-    return $this->_change_subscription($a_mboxes, 'unsubscribe');
+        // let this common function do the main work
+        return $this->_change_subscription($a_mboxes, 'unsubscribe');
     }
 
 
-  /**
-   * Create a new mailbox on the server and register it in local cache
-   *
-   * @param string  New mailbox name (as utf-7 string)
-   * @param boolean True if the new mailbox should be subscribed
-   * @param string  Name of the created mailbox, false on error
-   */
-  function create_mailbox($name, $subscribe=false)
+    /**
+     * Create a new mailbox on the server and register it in local cache
+     *
+     * @param string  New mailbox name (as utf-7 string)
+     * @param boolean True if the new mailbox should be subscribed
+     * @param string  Name of the created mailbox, false on error
+     */
+    function create_mailbox($name, $subscribe=false)
     {
-    $result = false;
+        $result = false;
     
-    // reduce mailbox name to 100 chars
-    $name = substr($name, 0, 100);
-    $abs_name = $this->mod_mailbox($name);
-    $result = iil_C_CreateFolder($this->conn, $abs_name);
+        // reduce mailbox name to 100 chars
+        $name = substr($name, 0, 100);
+        $abs_name = $this->mod_mailbox($name);
+        $result = $this->conn->createFolder($abs_name);
 
-    // try to subscribe it
-    if ($result && $subscribe)
-      $this->subscribe($name);
+        // try to subscribe it
+        if ($result && $subscribe)
+            $this->subscribe($name);
 
-    return $result ? $name : false;
+        return $result ? $name : false;
     }
 
 
-  /**
-   * Set a new name to an existing mailbox
-   *
-   * @param string Mailbox to rename (as utf-7 string)
-   * @param string New mailbox name (as utf-7 string)
-   * @return string Name of the renames mailbox, False on error
-   */
-  function rename_mailbox($mbox_name, $new_name)
+    /**
+     * Set a new name to an existing mailbox
+     *
+     * @param string Mailbox to rename (as utf-7 string)
+     * @param string New mailbox name (as utf-7 string)
+     * @return string Name of the renames mailbox, False on error
+     */
+    function rename_mailbox($mbox_name, $new_name)
     {
-    $result = false;
+        $result = false;
 
-    // encode mailbox name and reduce it to 100 chars
-    $name = substr($new_name, 0, 100);
+        // encode mailbox name and reduce it to 100 chars
+        $name = substr($new_name, 0, 100);
 
-    // make absolute path
-    $mailbox = $this->mod_mailbox($mbox_name);
-    $abs_name = $this->mod_mailbox($name);
+        // make absolute path
+        $mailbox = $this->mod_mailbox($mbox_name);
+        $abs_name = $this->mod_mailbox($name);
     
-    // check if mailbox is subscribed
-    $a_subscribed = $this->_list_mailboxes();
-    $subscribed = in_array($mailbox, $a_subscribed);
+        // check if mailbox is subscribed
+        $a_subscribed = $this->_list_mailboxes();
+        $subscribed = in_array($mailbox, $a_subscribed);
     
-    // unsubscribe folder
-    if ($subscribed)
-      iil_C_UnSubscribe($this->conn, $mailbox);
+        // unsubscribe folder
+        if ($subscribed)
+            $this->conn->unsubscribe($mailbox);
 
-    if (strlen($abs_name))
-      $result = iil_C_RenameFolder($this->conn, $mailbox, $abs_name);
+        if (strlen($abs_name))
+            $result = $this->conn->renameFolder($mailbox, $abs_name);
 
-    if ($result)
-      {
-      $delm = $this->get_hierarchy_delimiter();
+        if ($result) {
+            $delm = $this->get_hierarchy_delimiter();
       
-      // check if mailbox children are subscribed
-      foreach ($a_subscribed as $c_subscribed)
-        if (preg_match('/^'.preg_quote($mailbox.$delm, '/').'/', $c_subscribed))
-          {
-          iil_C_UnSubscribe($this->conn, $c_subscribed);
-          iil_C_Subscribe($this->conn, preg_replace('/^'.preg_quote($mailbox, '/').'/', $abs_name, $c_subscribed));
-          }
-
-      // clear cache
-      $this->clear_message_cache($mailbox.'.msg');
-      $this->clear_cache('mailboxes');      
-      }
+            // check if mailbox children are subscribed
+            foreach ($a_subscribed as $c_subscribed)
+                if (preg_match('/^'.preg_quote($mailbox.$delm, '/').'/', $c_subscribed)) {
+                    $this->conn->unsubscribe($c_subscribed);
+                    $this->conn->subscribe(preg_replace('/^'.preg_quote($mailbox, '/').'/',
+                        $abs_name, $c_subscribed));
+                }
+
+            // clear cache
+            $this->clear_message_cache($mailbox.'.msg');
+            $this->clear_cache('mailboxes');      
+        }
 
-    // try to subscribe it
-    if ($result && $subscribed)
-      iil_C_Subscribe($this->conn, $abs_name);
+        // try to subscribe it
+        if ($result && $subscribed)
+            $this->conn->subscribe($abs_name);
 
-    return $result ? $name : false;
+        return $result ? $name : false;
     }
 
 
-  /**
-   * Remove mailboxes from server
-   *
-   * @param string Mailbox name(s) string/array
-   * @return boolean True on success
-   */
-  function delete_mailbox($mbox_name)
+    /**
+     * Remove mailboxes from server
+     *
+     * @param string Mailbox name(s) string/array
+     * @return boolean True on success
+     */
+    function delete_mailbox($mbox_name)
     {
-    $deleted = false;
+        $deleted = false;
 
-    if (is_array($mbox_name))
-      $a_mboxes = $mbox_name;
-    else if (is_string($mbox_name) && strlen($mbox_name))
-      $a_mboxes = explode(',', $mbox_name);
+        if (is_array($mbox_name))
+            $a_mboxes = $mbox_name;
+        else if (is_string($mbox_name) && strlen($mbox_name))
+            $a_mboxes = explode(',', $mbox_name);
 
-    if (is_array($a_mboxes))
-      foreach ($a_mboxes as $mbox_name)
-        {
-        $mailbox = $this->mod_mailbox($mbox_name);
-        $sub_mboxes = iil_C_ListMailboxes($this->conn, $this->mod_mailbox(''),
-	  $mbox_name . $this->delimiter . '*');
+        if (is_array($a_mboxes)) {
+            foreach ($a_mboxes as $mbox_name) {
+                $mailbox = $this->mod_mailbox($mbox_name);
+                $sub_mboxes = $this->conn->listMailboxes($this->mod_mailbox(''),
+	            $mbox_name . $this->delimiter . '*');
 
-        // unsubscribe mailbox before deleting
-        iil_C_UnSubscribe($this->conn, $mailbox);
+                // unsubscribe mailbox before deleting
+                $this->conn->unsubscribe($mailbox);
 
-        // send delete command to server
-        $result = iil_C_DeleteFolder($this->conn, $mailbox);
-        if ($result >= 0) {
-          $deleted = true;
-          $this->clear_message_cache($mailbox.'.msg');
-	  }
+                // send delete command to server
+                $result = $this->conn->deleteFolder($mailbox);
+                if ($result >= 0) {
+                    $deleted = true;
+                    $this->clear_message_cache($mailbox.'.msg');
+	            }
 	  
-        foreach ($sub_mboxes as $c_mbox)
-          if ($c_mbox != 'INBOX') {
-            iil_C_UnSubscribe($this->conn, $c_mbox);
-            $result = iil_C_DeleteFolder($this->conn, $c_mbox);
-            if ($result >= 0) {
-              $deleted = true;
-    	      $this->clear_message_cache($c_mbox.'.msg');
+                foreach ($sub_mboxes as $c_mbox) {
+                    if ($c_mbox != 'INBOX') {
+                        $this->conn->unsubscribe($c_mbox);
+                        $result = $this->conn->deleteFolder($c_mbox);
+                        if ($result >= 0) {
+                            $deleted = true;
+    	                    $this->clear_message_cache($c_mbox.'.msg');
+                        }
+                    }
+                }
             }
-          }
         }
 
-    // clear mailboxlist cache
-    if ($deleted)
-      $this->clear_cache('mailboxes');
+        // clear mailboxlist cache
+        if ($deleted)
+            $this->clear_cache('mailboxes');
 
-    return $deleted;
+        return $deleted;
     }
 
 
-  /**
-   * Create all folders specified as default
-   */
-  function create_default_folders()
+    /**
+     * Create all folders specified as default
+     */
+    function create_default_folders()
     {
-    // create default folders if they do not exist
-    foreach ($this->default_folders as $folder)
-      {
-      if (!$this->mailbox_exists($folder))
-        $this->create_mailbox($folder, true);
-      else if (!$this->mailbox_exists($folder, true))
-        $this->subscribe($folder);
-      }
+        // create default folders if they do not exist
+        foreach ($this->default_folders as $folder) {
+            if (!$this->mailbox_exists($folder))
+                $this->create_mailbox($folder, true);
+            else if (!$this->mailbox_exists($folder, true))
+                $this->subscribe($folder);
+        }
     }
 
 
-  /**
-   * Checks if folder exists and is subscribed
-   *
-   * @param string   Folder name
-   * @param boolean  Enable subscription checking
-   * @return boolean TRUE or FALSE
-   */
-  function mailbox_exists($mbox_name, $subscription=false)
+    /**
+     * Checks if folder exists and is subscribed
+     *
+     * @param string   Folder name
+     * @param boolean  Enable subscription checking
+     * @return boolean TRUE or FALSE
+     */
+    function mailbox_exists($mbox_name, $subscription=false)
     {
-    if ($mbox_name) {
-      if ($mbox_name == 'INBOX')
-        return true;
+        if ($mbox_name) {
+            if ($mbox_name == 'INBOX')
+                return true;
 
-      if ($subscription) {
-        if ($a_folders = iil_C_ListSubscribed($this->conn, $this->mod_mailbox(''), $mbox_name))
-          return true;
-        }
-      else {
-        $a_folders = iil_C_ListMailboxes($this->conn, $this->mod_mailbox(''), $mbox_mbox);
+            if ($subscription) {
+                if ($a_folders = $this->conn->listSubscribed($this->mod_mailbox(''), $mbox_name))
+                    return true;
+            }
+            else {
+                $a_folders = $this->conn->listMailboxes($this->mod_mailbox(''), $mbox_mbox);
 	
-	if (is_array($a_folders) && in_array($this->mod_mailbox($mbox_name), $a_folders))
-          return true;
+	        if (is_array($a_folders) && in_array($this->mod_mailbox($mbox_name), $a_folders))
+                return true;
+            }
         }
-      }
 
-    return false;
+        return false;
     }
 
 
+    /**
+     * Modify folder name for input/output according to root dir and namespace
+     *
+     * @param string  Folder name
+     * @param string  Mode
+     * @return string Folder name
+     */
+    function mod_mailbox($mbox_name, $mode='in')
+    {
+        if ($mbox_name == 'INBOX')
+            return $mbox_name;
+
+        if (!empty($this->root_dir)) {
+            if ($mode=='in')
+                $mbox_name = $this->root_dir.$this->delimiter.$mbox_name;
+            else if (!empty($mbox_name)) // $mode=='out'
+                $mbox_name = substr($mbox_name, strlen($this->root_dir)+1);
+        }
+    
+        return $mbox_name;
+    }
+
 
-  /* --------------------------------
-   *   internal caching methods
-   * --------------------------------*/
+    /* --------------------------------
+     *   internal caching methods
+     * --------------------------------*/
 
-  /**
-   * @access private
-   */
-  function set_caching($set)
+    /**
+     * @access public
+     */
+    function set_caching($set)
     {
-    if ($set && is_object($this->db))
-      $this->caching_enabled = true;
-    else
-      $this->caching_enabled = false;
+        if ($set && is_object($this->db))
+            $this->caching_enabled = true;
+        else
+            $this->caching_enabled = false;
     }
 
-  /**
-   * @access private
-   */
-  function get_cache($key)
+    /**
+     * @access public
+     */
+    function get_cache($key)
     {
-    // read cache (if it was not read before)
-    if (!count($this->cache) && $this->caching_enabled)
-      {
-      return $this->_read_cache_record($key);
-      }
+        // read cache (if it was not read before)
+        if (!count($this->cache) && $this->caching_enabled) {
+            return $this->_read_cache_record($key);
+        }
     
-    return $this->cache[$key];
+        return $this->cache[$key];
     }
 
-  /**
-   * @access private
-   */
-  function update_cache($key, $data)
+    /**
+     * @access private
+     */
+    private function update_cache($key, $data)
     {
-    $this->cache[$key] = $data;
-    $this->cache_changed = true;
-    $this->cache_changes[$key] = true;
+        $this->cache[$key] = $data;
+        $this->cache_changed = true;
+        $this->cache_changes[$key] = true;
     }
 
-  /**
-   * @access private
-   */
-  function write_cache()
+    /**
+     * @access private
+     */
+    private function write_cache()
     {
-    if ($this->caching_enabled && $this->cache_changed)
-      {
-      foreach ($this->cache as $key => $data)
-        {
-        if ($this->cache_changes[$key])
-          $this->_write_cache_record($key, serialize($data));
-        }
-      }    
-    }
-
-  /**
-   * @access private
-   */
-  function clear_cache($key=NULL)
-    {
-    if (!$this->caching_enabled)
-      return;
-    
-    if ($key===NULL)
-      {
-      foreach ($this->cache as $key => $data)
-        $this->_clear_cache_record($key);
-
-      $this->cache = array();
-      $this->cache_changed = false;
-      $this->cache_changes = array();
-      }
-    else
-      {
-      $this->_clear_cache_record($key);
-      $this->cache_changes[$key] = false;
-      unset($this->cache[$key]);
-      }
-    }
-
-  /**
-   * @access private
-   */
-  private function _read_cache_record($key)
-    {
-    if ($this->db)
-      {
-      // get cached data from DB
-      $sql_result = $this->db->query(
-        "SELECT cache_id, data, cache_key
-         FROM ".get_table_name('cache')."
-         WHERE  user_id=?
-	 AND cache_key LIKE 'IMAP.%'",
-        $_SESSION['user_id']);
-
-      while ($sql_arr = $this->db->fetch_assoc($sql_result))
-        {
-	$sql_key = preg_replace('/^IMAP\./', '', $sql_arr['cache_key']);
-        $this->cache_keys[$sql_key] = $sql_arr['cache_id'];
-	if (!isset($this->cache[$sql_key]))
-	  $this->cache[$sql_key] = $sql_arr['data'] ? unserialize($sql_arr['data']) : false;
-        }
-      }
-
-    return $this->cache[$key];
-    }
-
-  /**
-   * @access private
-   */
-  private function _write_cache_record($key, $data)
-    {
-    if (!$this->db)
-      return false;
-
-    // update existing cache record
-    if ($this->cache_keys[$key])
-      {
-      $this->db->query(
-        "UPDATE ".get_table_name('cache')."
-         SET    created=". $this->db->now().", data=?
-         WHERE  user_id=?
-         AND    cache_key=?",
-        $data,
-        $_SESSION['user_id'],
-        'IMAP.'.$key);
-      }
-    // add new cache record
-    else
-      {
-      $this->db->query(
-        "INSERT INTO ".get_table_name('cache')."
-         (created, user_id, cache_key, data)
-         VALUES (".$this->db->now().", ?, ?, ?)",
-        $_SESSION['user_id'],
-        'IMAP.'.$key,
-        $data);
-
-      // get cache entry ID for this key
-      $sql_result = $this->db->query(
-        "SELECT cache_id
-         FROM ".get_table_name('cache')."
-         WHERE  user_id=?
-         AND    cache_key=?",
-        $_SESSION['user_id'],
-        'IMAP.'.$key);
-                                     
-        if ($sql_arr = $this->db->fetch_assoc($sql_result))
-          $this->cache_keys[$key] = $sql_arr['cache_id'];
-      }
+        if ($this->caching_enabled && $this->cache_changed) {
+            foreach ($this->cache as $key => $data) {
+                if ($this->cache_changes[$key])
+                    $this->_write_cache_record($key, serialize($data));
+            }
+        }
     }
 
-  /**
-   * @access private
-   */
-  private function _clear_cache_record($key)
+    /**
+     * @access public
+     */
+    function clear_cache($key=NULL)
     {
-    $this->db->query(
-      "DELETE FROM ".get_table_name('cache')."
-       WHERE  user_id=?
-       AND    cache_key=?",
-      $_SESSION['user_id'],
-      'IMAP.'.$key);
+        if (!$this->caching_enabled)
+            return;
+    
+        if ($key===NULL) {
+            foreach ($this->cache as $key => $data)
+                $this->_clear_cache_record($key);
+
+            $this->cache = array();
+            $this->cache_changed = false;
+            $this->cache_changes = array();
+        }
+        else {
+            $this->_clear_cache_record($key);
+            $this->cache_changes[$key] = false;
+            unset($this->cache[$key]);
+        }
+    }
+
+    /**
+     * @access private
+     */
+    private function _read_cache_record($key)
+    {
+        if ($this->db) {
+            // get cached data from DB
+            $sql_result = $this->db->query(
+                "SELECT cache_id, data, cache_key ".
+                "FROM ".get_table_name('cache').
+                " WHERE user_id=? ".
+	            "AND cache_key LIKE 'IMAP.%'",
+                $_SESSION['user_id']);
+
+            while ($sql_arr = $this->db->fetch_assoc($sql_result)) {
+	            $sql_key = preg_replace('/^IMAP\./', '', $sql_arr['cache_key']);
+                $this->cache_keys[$sql_key] = $sql_arr['cache_id'];
+	            if (!isset($this->cache[$sql_key]))
+	                $this->cache[$sql_key] = $sql_arr['data'] ? unserialize($sql_arr['data']) : false;
+            }
+        }
+
+        return $this->cache[$key];
+    }
+
+    /**
+     * @access private
+     */
+    private function _write_cache_record($key, $data)
+    {
+        if (!$this->db)
+            return false;
+
+        // update existing cache record
+        if ($this->cache_keys[$key]) {
+            $this->db->query(
+                "UPDATE ".get_table_name('cache').
+                " SET created=". $this->db->now().", data=? ".
+                "WHERE user_id=? ".
+                "AND cache_key=?",
+                $data,
+                $_SESSION['user_id'],
+                'IMAP.'.$key);
+        }
+        // add new cache record
+        else {
+            $this->db->query(
+                "INSERT INTO ".get_table_name('cache').
+                " (created, user_id, cache_key, data) ".
+                "VALUES (".$this->db->now().", ?, ?, ?)",
+                $_SESSION['user_id'],
+                'IMAP.'.$key,
+                $data);
+
+            // get cache entry ID for this key
+            $sql_result = $this->db->query(
+                "SELECT cache_id ".
+                "FROM ".get_table_name('cache').
+                " WHERE user_id=? ".
+                "AND cache_key=?",
+                $_SESSION['user_id'],
+                'IMAP.'.$key);
+
+            if ($sql_arr = $this->db->fetch_assoc($sql_result))
+                $this->cache_keys[$key] = $sql_arr['cache_id'];
+        }
+    }
+
+    /**
+     * @access private
+     */
+    private function _clear_cache_record($key)
+    {
+        $this->db->query(
+            "DELETE FROM ".get_table_name('cache').
+            " WHERE user_id=? ".
+            "AND cache_key=?",
+            $_SESSION['user_id'],
+            'IMAP.'.$key);
       
-    unset($this->cache_keys[$key]);
+        unset($this->cache_keys[$key]);
     }
 
 
 
-  /* --------------------------------
-   *   message caching methods
-   * --------------------------------*/
+    /* --------------------------------
+     *   message caching methods
+     * --------------------------------*/
    
-
-  /**
-   * Checks if the cache is up-to-date
-   *
-   * @param string Mailbox name
-   * @param string Internal cache key
-   * @return int   Cache status: -3 = off, -2 = incomplete, -1 = dirty
-   */
-  private function check_cache_status($mailbox, $cache_key)
-  {
-    if (!$this->caching_enabled)
-      return -3;
-
-    $cache_index = $this->get_message_cache_index($cache_key);
-    $msg_count = $this->_messagecount($mailbox);
-    $cache_count = count($cache_index);
-
-    // empty mailbox
-    if (!$msg_count)
-      return $cache_count ? -2 : 1;
-
-    // @TODO: We've got one big performance problem in cache status checking method
-    // E.g. mailbox contains 1000 messages, in cache table we've got first 100
-    // of them. Now if we want to display only that 100 (which we've got)
-    // check_cache_status returns 'incomplete' and messages are fetched
-    // from IMAP instead of DB.
-
-    if ($cache_count==$msg_count) {
-      if ($this->skip_deleted) {
-	$h_index = iil_C_FetchHeaderIndex($this->conn, $mailbox, "1:*", 'UID', $this->skip_deleted);
-
-	if (sizeof($h_index) == $cache_count) {
-	  $cache_index = array_flip($cache_index);
-	  foreach ($h_index as $idx => $uid)
-            unset($cache_index[$uid]);
-
-	  if (empty($cache_index))
-	    return 1;
-	}
-	return -2;
-      } else {
-        // get UID of message with highest index
-        $uid = iil_C_ID2UID($this->conn, $mailbox, $msg_count);
-        $cache_uid = array_pop($cache_index);
+    /**
+     * Checks if the cache is up-to-date
+     *
+     * @param string Mailbox name
+     * @param string Internal cache key
+     * @return int   Cache status: -3 = off, -2 = incomplete, -1 = dirty, 1 = OK
+     */
+    private function check_cache_status($mailbox, $cache_key)
+    {
+        if (!$this->caching_enabled)
+            return -3;
+
+        $cache_index = $this->get_message_cache_index($cache_key);
+        $msg_count = $this->_messagecount($mailbox);
+        $cache_count = count($cache_index);
+
+        // empty mailbox
+        if (!$msg_count)
+            return $cache_count ? -2 : 1;
+
+        // @TODO: We've got one big performance problem in cache status checking method
+        // E.g. mailbox contains 1000 messages, in cache table we've got first 100
+        // of them. Now if we want to display only that 100 (which we've got)
+        // check_cache_status returns 'incomplete' and messages are fetched
+        // from IMAP instead of DB.
+
+        if ($cache_count==$msg_count) {
+            if ($this->skip_deleted) {
+	            $h_index = $this->conn->fetchHeaderIndex($mailbox, "1:*", 'UID', $this->skip_deleted);
+
+                if (empty($h_index))
+                    return -2;
+
+	            if (sizeof($h_index) == $cache_count) {
+	                $cache_index = array_flip($cache_index);
+	                foreach ($h_index as $idx => $uid)
+                        unset($cache_index[$uid]);
+
+	                if (empty($cache_index))
+	                    return 1;
+	            }
+	            return -2;
+            } else {
+                // get UID of message with highest index
+                $uid = $this->conn->ID2UID($mailbox, $msg_count);
+                $cache_uid = array_pop($cache_index);
       
-        // uids of highest message matches -> cache seems OK
-        if ($cache_uid == $uid)
-          return 1;
-      }
-      // cache is dirty
-      return -1;
-    }
-    // if cache count differs less than 10% report as dirty
-    else if (abs($msg_count - $cache_count) < $msg_count/10)
-      return -1;
-    else
-      return -2;
-  }
-
-  /**
-   * @access private
-   */
-  private function get_message_cache($key, $from, $to, $sort_field, $sort_order)
-    {
-    $cache_key = "$key:$from:$to:$sort_field:$sort_order";
-    
-    $config = rcmail::get_instance()->config;
-
-    // use idx sort as default sorting
-    if (!$sort_field || !in_array($sort_field, $this->db_header_fields)) {
-      $sort_field = 'idx';
-      }
-    
-    if ($this->caching_enabled && !isset($this->cache[$cache_key]))
-      {
-      $this->cache[$cache_key] = array();
-      $sql_result = $this->db->limitquery(
-        "SELECT idx, uid, headers
-         FROM ".get_table_name('messages')."
-         WHERE  user_id=?
-         AND    cache_key=?
-         ORDER BY ".$this->db->quoteIdentifier($sort_field)." ".strtoupper($sort_order),
-        $from,
-        $to-$from,
-        $_SESSION['user_id'],
-        $key);
-
-      while ($sql_arr = $this->db->fetch_assoc($sql_result))
-        {
-        $uid = $sql_arr['uid'];
-        $this->cache[$cache_key][$uid] =  $this->db->decode(unserialize($sql_arr['headers']));
+                // uids of highest message matches -> cache seems OK
+                if ($cache_uid == $uid)
+                    return 1;
+            }
+            // cache is dirty
+            return -1;
+        }
+        // if cache count differs less than 10% report as dirty
+        else if (abs($msg_count - $cache_count) < $msg_count/10)
+            return -1;
+        else
+            return -2;
+    }
 
-        // featch headers if unserialize failed
-        if (empty($this->cache[$cache_key][$uid]))
-          $this->cache[$cache_key][$uid] = iil_C_FetchHeader($this->conn, preg_replace('/.msg$/', '', $key), $uid, true, $this->fetch_add_headers);
+    /**
+     * @access private
+     */
+    private function get_message_cache($key, $from, $to, $sort_field, $sort_order)
+    {
+        $cache_key = "$key:$from:$to:$sort_field:$sort_order";
+    
+        // use idx sort as default sorting
+        if (!$sort_field || !in_array($sort_field, $this->db_header_fields)) {
+            $sort_field = 'idx';
+        }
+    
+        if ($this->caching_enabled && !isset($this->cache[$cache_key])) {
+            $this->cache[$cache_key] = array();
+            $sql_result = $this->db->limitquery(
+                "SELECT idx, uid, headers".
+                " FROM ".get_table_name('messages').
+                " WHERE user_id=?".
+                " AND cache_key=?".
+                " ORDER BY ".$this->db->quoteIdentifier($sort_field)." ".strtoupper($sort_order),
+                $from,
+                $to - $from,
+                $_SESSION['user_id'],
+                $key);
+
+            while ($sql_arr = $this->db->fetch_assoc($sql_result)) {
+                $uid = $sql_arr['uid'];
+                $this->cache[$cache_key][$uid] =  $this->db->decode(unserialize($sql_arr['headers']));
+
+                // featch headers if unserialize failed
+                if (empty($this->cache[$cache_key][$uid]))
+                    $this->cache[$cache_key][$uid] = $this->conn->fetchHeader(
+                            preg_replace('/.msg$/', '', $key), $uid, true, $this->fetch_add_headers);
+            }
         }
-      }
 
-    return $this->cache[$cache_key];
+        return $this->cache[$cache_key];
     }
 
-  /**
-   * @access private
-   */
-  private function &get_cached_message($key, $uid)
+    /**
+     * @access private
+     */
+    private function &get_cached_message($key, $uid)
     {
-    $internal_key = 'message';
+        $internal_key = 'message';
     
-    if ($this->caching_enabled && !isset($this->icache[$internal_key][$uid]))
-      {
-      $sql_result = $this->db->query(
-        "SELECT idx, headers, structure
-         FROM ".get_table_name('messages')."
-         WHERE  user_id=?
-         AND    cache_key=?
-         AND    uid=?",
-        $_SESSION['user_id'],
-        $key,
-        $uid);
+        if ($this->caching_enabled && !isset($this->icache[$internal_key][$uid])) {
+            $sql_result = $this->db->query(
+                "SELECT idx, headers, structure".
+                " FROM ".get_table_name('messages').
+                " WHERE user_id=?".
+                " AND cache_key=?".
+                " AND uid=?",
+                $_SESSION['user_id'],
+                $key,
+                $uid);
 
-      if ($sql_arr = $this->db->fetch_assoc($sql_result))
-        {
-	$this->uid_id_map[preg_replace('/\.msg$/', '', $key)][$uid] = $sql_arr['idx'];
-        $this->icache[$internal_key][$uid] = $this->db->decode(unserialize($sql_arr['headers']));
-        if (is_object($this->icache[$internal_key][$uid]) && !empty($sql_arr['structure']))
-          $this->icache[$internal_key][$uid]->structure = $this->db->decode(unserialize($sql_arr['structure']));
+            if ($sql_arr = $this->db->fetch_assoc($sql_result)) {
+	            $this->uid_id_map[preg_replace('/\.msg$/', '', $key)][$uid] = $sql_arr['idx'];
+                $this->icache[$internal_key][$uid] = $this->db->decode(unserialize($sql_arr['headers']));
+                if (is_object($this->icache[$internal_key][$uid]) && !empty($sql_arr['structure']))
+                    $this->icache[$internal_key][$uid]->structure = $this->db->decode(unserialize($sql_arr['structure']));
+            }
         }
-      }
 
-    return $this->icache[$internal_key][$uid];
+        return $this->icache[$internal_key][$uid];
     }
 
-  /**
-   * @access private
-   */  
-  private function get_message_cache_index($key, $force=false, $sort_field='idx', $sort_order='ASC')
+    /**
+     * @access private
+     */  
+    private function get_message_cache_index($key, $force=false, $sort_field='idx', $sort_order='ASC')
     {
-    static $sa_message_index = array();
+        static $sa_message_index = array();
     
-    // empty key -> empty array
-    if (!$this->caching_enabled || empty($key))
-      return array();
+        // empty key -> empty array
+        if (!$this->caching_enabled || empty($key))
+            return array();
     
-    if (!empty($sa_message_index[$key]) && !$force)
-      return $sa_message_index[$key];
+        if (!empty($sa_message_index[$key]) && !$force)
+            return $sa_message_index[$key];
 
-    // use idx sort as default
-    if (!$sort_field || !in_array($sort_field, $this->db_header_fields))
-      $sort_field = 'idx';
+        // use idx sort as default
+        if (!$sort_field || !in_array($sort_field, $this->db_header_fields))
+            $sort_field = 'idx';
     
-    $sa_message_index[$key] = array();
-    $sql_result = $this->db->query(
-      "SELECT idx, uid
-       FROM ".get_table_name('messages')."
-       WHERE  user_id=?
-       AND    cache_key=?
-       ORDER BY ".$this->db->quote_identifier($sort_field)." ".$sort_order,
-      $_SESSION['user_id'],
-      $key);
+        $sa_message_index[$key] = array();
+        $sql_result = $this->db->query(
+            "SELECT idx, uid".
+            " FROM ".get_table_name('messages').
+            " WHERE user_id=?".
+            " AND cache_key=?".
+            " ORDER BY ".$this->db->quote_identifier($sort_field)." ".$sort_order,
+            $_SESSION['user_id'],
+            $key);
 
-    while ($sql_arr = $this->db->fetch_assoc($sql_result))
-      $sa_message_index[$key][$sql_arr['idx']] = $sql_arr['uid'];
+        while ($sql_arr = $this->db->fetch_assoc($sql_result))
+            $sa_message_index[$key][$sql_arr['idx']] = $sql_arr['uid'];
       
-    return $sa_message_index[$key];
-    }
-
-  /**
-   * @access private
-   */
-  private function add_message_cache($key, $index, $headers, $struct=null, $force=false)
-    {
-    if (empty($key) || !is_object($headers) || empty($headers->uid))
-        return;
-
-    // add to internal (fast) cache
-    $this->icache['message'][$headers->uid] = clone $headers;
-    $this->icache['message'][$headers->uid]->structure = $struct;
-
-    // no further caching
-    if (!$this->caching_enabled)
-      return;
-    
-    // check for an existing record (probly headers are cached but structure not)
-    if (!$force) {
-      $sql_result = $this->db->query(
-        "SELECT message_id
-         FROM ".get_table_name('messages')."
-         WHERE  user_id=?
-         AND    cache_key=?
-         AND    uid=?",
-        $_SESSION['user_id'],
-        $key,
-        $headers->uid);
-      if ($sql_arr = $this->db->fetch_assoc($sql_result))
-        $message_id = $sql_arr['message_id'];
-      }
-
-    // update cache record
-    if ($message_id)
-      {
-      $this->db->query(
-        "UPDATE ".get_table_name('messages')."
-         SET   idx=?, headers=?, structure=?
-         WHERE message_id=?",
-        $index,
-        serialize($this->db->encode(clone $headers)),
-        is_object($struct) ? serialize($this->db->encode(clone $struct)) : NULL,
-        $message_id
-        );
-      }
-    else  // insert new record
-      {
-      $this->db->query(
-        "INSERT INTO ".get_table_name('messages')."
-         (user_id, del, cache_key, created, idx, uid, subject, ".$this->db->quoteIdentifier('from').", ".$this->db->quoteIdentifier('to').", cc, date, size, headers, structure)
-         VALUES (?, 0, ?, ".$this->db->now().", ?, ?, ?, ?, ?, ?, ".$this->db->fromunixtime($headers->timestamp).", ?, ?, ?)",
-        $_SESSION['user_id'],
-        $key,
-        $index,
-        $headers->uid,
-        (string)mb_substr($this->db->encode($this->decode_header($headers->subject, true)), 0, 128),
-        (string)mb_substr($this->db->encode($this->decode_header($headers->from, true)), 0, 128),
-        (string)mb_substr($this->db->encode($this->decode_header($headers->to, true)), 0, 128),
-        (string)mb_substr($this->db->encode($this->decode_header($headers->cc, true)), 0, 128),
-        (int)$headers->size,
-        serialize($this->db->encode(clone $headers)),
-        is_object($struct) ? serialize($this->db->encode(clone $struct)) : NULL
-        );
-      }
-    }
-    
-  /**
-   * @access private
-   */
-  private function remove_message_cache($key, $ids, $idx=false)
-    {
-    if (!$this->caching_enabled)
-      return;
-    
-    $this->db->query(
-      "DELETE FROM ".get_table_name('messages')."
-      WHERE user_id=?
-      AND cache_key=?
-      AND ".($idx ? "idx" : "uid")." IN (".$this->db->array2list($ids, 'integer').")",
-      $_SESSION['user_id'],
-      $key);
-    }
-
-  /**
-   * @access private
-   */
-  private function clear_message_cache($key, $start_index=1)
-    {
-    if (!$this->caching_enabled)
-      return;
-    
-    $this->db->query(
-      "DELETE FROM ".get_table_name('messages')."
-       WHERE user_id=?
-       AND cache_key=?
-       AND idx>=?",
-      $_SESSION['user_id'], $key, $start_index);
-    }
-
-  /**
-   * @access private
-   */
-  private function get_message_cache_index_min($key, $uids=NULL)
-    {
-    if (!$this->caching_enabled)
-      return;
-    
-    if (!empty($uids) && !is_array($uids)) {
-      if ($uids == '*' || $uids == '1:*')
-        $uids = NULL;
-      else
-        $uids = explode(',', $uids);
-      }
-
-    $sql_result = $this->db->query(
-      "SELECT MIN(idx) AS minidx
-      FROM ".get_table_name('messages')."
-      WHERE  user_id=?
-      AND    cache_key=?"
-      .(!empty($uids) ? " AND uid IN (".$this->db->array2list($uids, 'integer').")" : ''),
-      $_SESSION['user_id'],
-      $key);
-
-    if ($sql_arr = $this->db->fetch_assoc($sql_result))
-      return $sql_arr['minidx'];
-    else
-      return 0;  
-    }
-
-
-  /* --------------------------------
-   *   encoding/decoding methods
-   * --------------------------------*/
-
-  /**
-   * Split an address list into a structured array list
-   *
-   * @param string  Input string
-   * @param int     List only this number of addresses
-   * @param boolean Decode address strings
-   * @return array  Indexed list of addresses
-   */
-  function decode_address_list($input, $max=null, $decode=true)
-    {
-    $a = $this->_parse_address_list($input, $decode);
-    $out = array();
-    // Special chars as defined by RFC 822 need to in quoted string (or escaped).
-    $special_chars = '[\(\)\<\>\\\.\[\]@,;:"]';
-    
-    if (!is_array($a))
-      return $out;
-
-    $c = count($a);
-    $j = 0;
-
-    foreach ($a as $val)
-      {
-      $j++;
-      $address = trim($val['address']);
-      $name = trim($val['name']);
-
-      if (preg_match('/^[\'"]/', $name) && preg_match('/[\'"]$/', $name))
-        $name = preg_replace(array('/^[\'"]/', '/[\'"]$/'), '', $name);
-
-      if ($name && $address && $name != $address)
-        $string = sprintf('%s <%s>', preg_match("/$special_chars/", $name) ? '"'.addcslashes($name, '"').'"' : $name, $address);
-      else if ($address)
-        $string = $address;
-      else if ($name)
-        $string = $name;
+        return $sa_message_index[$key];
+    }
+
+    /**
+     * @access private
+     */
+    private function add_message_cache($key, $index, $headers, $struct=null, $force=false)
+    {
+        if (empty($key) || !is_object($headers) || empty($headers->uid))
+            return;
+
+        // add to internal (fast) cache
+        $this->icache['message'][$headers->uid] = clone $headers;
+        $this->icache['message'][$headers->uid]->structure = $struct;
+
+        // no further caching
+        if (!$this->caching_enabled)
+            return;
+    
+        // check for an existing record (probly headers are cached but structure not)
+        if (!$force) {
+            $sql_result = $this->db->query(
+                "SELECT message_id".
+                " FROM ".get_table_name('messages').
+                " WHERE user_id=?".
+                " AND cache_key=?".
+                " AND uid=?",
+                $_SESSION['user_id'],
+                $key,
+                $headers->uid);
+
+            if ($sql_arr = $this->db->fetch_assoc($sql_result))
+                $message_id = $sql_arr['message_id'];
+        }
+
+        // update cache record
+        if ($message_id) {
+            $this->db->query(
+                "UPDATE ".get_table_name('messages').
+                " SET idx=?, headers=?, structure=?".
+                " WHERE message_id=?",
+                $index,
+                serialize($this->db->encode(clone $headers)),
+                is_object($struct) ? serialize($this->db->encode(clone $struct)) : NULL,
+                $message_id
+            );
+        }
+        else { // insert new record
+            $this->db->query(
+                "INSERT INTO ".get_table_name('messages').
+                " (user_id, del, cache_key, created, idx, uid, subject, ".
+                $this->db->quoteIdentifier('from').", ".
+                $this->db->quoteIdentifier('to').", ".
+                "cc, date, size, headers, structure)".
+                " VALUES (?, 0, ?, ".$this->db->now().", ?, ?, ?, ?, ?, ?, ".
+                $this->db->fromunixtime($headers->timestamp).", ?, ?, ?)",
+                $_SESSION['user_id'],
+                $key,
+                $index,
+                $headers->uid,
+                (string)mb_substr($this->db->encode($this->decode_header($headers->subject, true)), 0, 128),
+                (string)mb_substr($this->db->encode($this->decode_header($headers->from, true)), 0, 128),
+                (string)mb_substr($this->db->encode($this->decode_header($headers->to, true)), 0, 128),
+                (string)mb_substr($this->db->encode($this->decode_header($headers->cc, true)), 0, 128),
+                (int)$headers->size,
+                serialize($this->db->encode(clone $headers)),
+                is_object($struct) ? serialize($this->db->encode(clone $struct)) : NULL
+            );
+        }
+    }
+    
+    /**
+     * @access private
+     */
+    private function remove_message_cache($key, $ids, $idx=false)
+    {
+        if (!$this->caching_enabled)
+            return;
+    
+        $this->db->query(
+            "DELETE FROM ".get_table_name('messages').
+            " WHERE user_id=?".
+            " AND cache_key=?".
+            " AND ".($idx ? "idx" : "uid")." IN (".$this->db->array2list($ids, 'integer').")",
+            $_SESSION['user_id'],
+            $key);
+    }
+
+    /**
+     * @access private
+     */
+    private function clear_message_cache($key, $start_index=1)
+    {
+        if (!$this->caching_enabled)
+            return;
+    
+        $this->db->query(
+            "DELETE FROM ".get_table_name('messages').
+            " WHERE user_id=?".
+            " AND cache_key=?".
+            " AND idx>=?",
+            $_SESSION['user_id'], $key, $start_index);
+    }
+
+    /**
+     * @access private
+     */
+    private function get_message_cache_index_min($key, $uids=NULL)
+    {
+        if (!$this->caching_enabled)
+            return;
+    
+        if (!empty($uids) && !is_array($uids)) {
+            if ($uids == '*' || $uids == '1:*')
+                $uids = NULL;
+            else
+                $uids = explode(',', $uids);
+        }
+
+        $sql_result = $this->db->query(
+            "SELECT MIN(idx) AS minidx".
+            " FROM ".get_table_name('messages').
+            " WHERE  user_id=?".
+            " AND    cache_key=?"
+            .(!empty($uids) ? " AND uid IN (".$this->db->array2list($uids, 'integer').")" : ''),
+            $_SESSION['user_id'],
+            $key);
+
+        if ($sql_arr = $this->db->fetch_assoc($sql_result))
+            return $sql_arr['minidx'];
+        else
+            return 0;  
+    }
+
+
+    /* --------------------------------
+     *   encoding/decoding methods
+     * --------------------------------*/
+
+    /**
+     * Split an address list into a structured array list
+     *
+     * @param string  Input string
+     * @param int     List only this number of addresses
+     * @param boolean Decode address strings
+     * @return array  Indexed list of addresses
+     */
+    function decode_address_list($input, $max=null, $decode=true)
+    {
+        $a = $this->_parse_address_list($input, $decode);
+        $out = array();
+        // Special chars as defined by RFC 822 need to in quoted string (or escaped).
+        $special_chars = '[\(\)\<\>\\\.\[\]@,;:"]';
+    
+        if (!is_array($a))
+            return $out;
+
+        $c = count($a);
+        $j = 0;
+
+        foreach ($a as $val) {
+            $j++;
+            $address = trim($val['address']);
+            $name = trim($val['name']);
+
+            if (preg_match('/^[\'"]/', $name) && preg_match('/[\'"]$/', $name))
+                $name = preg_replace(array('/^[\'"]/', '/[\'"]$/'), '', $name);
+
+            if ($name && $address && $name != $address)
+                $string = sprintf('%s <%s>', preg_match("/$special_chars/", $name) ? '"'.addcslashes($name, '"').'"' : $name, $address);
+            else if ($address)
+                $string = $address;
+            else if ($name)
+                $string = $name;
       
-      $out[$j] = array('name' => $name,
-                       'mailto' => $address,
-                       'string' => $string);
+            $out[$j] = array('name' => $name,
+                'mailto' => $address,
+                'string' => $string
+            );
 
-      if ($max && $j==$max)
-        break;
-      }
+            if ($max && $j==$max)
+                break;
+        }
     
-    return $out;
+        return $out;
     }
   
   
-  /**
-   * Decode a Microsoft Outlook TNEF part (winmail.dat)
-   *
-   * @param object rcube_message_part Message part to decode
-   * @param string UID of the message
-   * @return array List of rcube_message_parts extracted from windmail.dat
-   */
-  function tnef_decode(&$part, $uid)
-  {
-    if (!isset($part->body))
-      $part->body = $this->get_message_part($uid, $part->mime_id, $part);
-
-    $pid = 0;
-    $tnef_parts = array();
-    $tnef_arr = tnef_decode($part->body);
-    foreach ($tnef_arr as $winatt) {
-      $tpart = new rcube_message_part;
-      $tpart->filename = $winatt["name"];
-      $tpart->encoding = 'stream';
-      $tpart->ctype_primary = $winatt["type0"];
-      $tpart->ctype_secondary = $winatt["type1"];
-      $tpart->mimetype = strtolower($winatt["type0"] . "/" . $winatt["type1"]);
-      $tpart->mime_id = "winmail." . $part->mime_id . ".$pid";
-      $tpart->size = $winatt["size"];
-      $tpart->body = $winatt['stream'];
-      
-      $tnef_parts[] = $tpart;
-      $pid++;
-    }
+    /**
+     * Decode a Microsoft Outlook TNEF part (winmail.dat)
+     *
+     * @param object rcube_message_part Message part to decode
+     * @param string UID of the message
+     * @return array List of rcube_message_parts extracted from windmail.dat
+     */
+    function tnef_decode(&$part, $uid)
+    {
+        if (!isset($part->body))
+            $part->body = $this->get_message_part($uid, $part->mime_id, $part);
+
+        $pid = 0;
+        $tnef_parts = array();
+        $tnef_arr = tnef_decode($part->body);
+    
+        foreach ($tnef_arr as $winatt) {
+            $tpart = new rcube_message_part;
+            $tpart->filename = $winatt["name"];
+            $tpart->encoding = 'stream';
+            $tpart->ctype_primary = $winatt["type0"];
+            $tpart->ctype_secondary = $winatt["type1"];
+            $tpart->mimetype = strtolower($winatt["type0"] . "/" . $winatt["type1"]);
+            $tpart->mime_id = "winmail." . $part->mime_id . ".$pid";
+            $tpart->size = $winatt["size"];
+            $tpart->body = $winatt['stream'];
+
+            $tnef_parts[] = $tpart;
+            $pid++;
+        }
 
-    return $tnef_parts;
-  }
+        return $tnef_parts;
+    }
 
 
-  /**
-   * Decode a message header value
-   *
-   * @param string  Header value
-   * @param boolean Remove quotes if necessary
-   * @return string Decoded string
-   */
-  function decode_header($input, $remove_quotes=false)
+    /**
+     * Decode a message header value
+     *
+     * @param string  Header value
+     * @param boolean Remove quotes if necessary
+     * @return string Decoded string
+     */
+    function decode_header($input, $remove_quotes=false)
     {
-    $str = rcube_imap::decode_mime_string((string)$input, $this->default_charset);
-    if ($str{0}=='"' && $remove_quotes)
-      $str = str_replace('"', '', $str);
+        $str = rcube_imap::decode_mime_string((string)$input, $this->default_charset);
+        if ($str{0}=='"' && $remove_quotes)
+            $str = str_replace('"', '', $str);
     
-    return $str;
+        return $str;
     }
 
 
-  /**
-   * Decode a mime-encoded string to internal charset
-   *
-   * @param string $input    Header value
-   * @param string $fallback Fallback charset if none specified
-   *
-   * @return string Decoded string
-   * @static
-   */
-  public static function decode_mime_string($input, $fallback=null)
+    /**
+     * Decode a mime-encoded string to internal charset
+     *
+     * @param string $input    Header value
+     * @param string $fallback Fallback charset if none specified
+     *
+     * @return string Decoded string
+     * @static
+     */
+    public static function decode_mime_string($input, $fallback=null)
     {
-    // Initialize variable
-    $out = '';
+        // Initialize variable
+        $out = '';
 
-    // Iterate instead of recursing, this way if there are too many values we don't have stack overflows
-    // rfc: all line breaks or other characters not found 
-    // in the Base64 Alphabet must be ignored by decoding software
-    // delete all blanks between MIME-lines, differently we can 
-    // receive unnecessary blanks and broken utf-8 symbols
-    $input = preg_replace("/\?=\s+=\?/", '?==?', $input);
+        // Iterate instead of recursing, this way if there are too many values we don't have stack overflows
+        // rfc: all line breaks or other characters not found 
+        // in the Base64 Alphabet must be ignored by decoding software
+        // delete all blanks between MIME-lines, differently we can 
+        // receive unnecessary blanks and broken utf-8 symbols
+        $input = preg_replace("/\?=\s+=\?/", '?==?', $input);
 
-    // Check if there is stuff to decode
-    if (strpos($input, '=?') !== false) {
-      // Loop through the string to decode all occurences of =? ?= into the variable $out 
-      while(($pos = strpos($input, '=?')) !== false) {
-        // Append everything that is before the text to be decoded
-        $out .= substr($input, 0, $pos);
+        // Check if there is stuff to decode
+        if (strpos($input, '=?') !== false) {
+            // Loop through the string to decode all occurences of =? ?= into the variable $out 
+            while(($pos = strpos($input, '=?')) !== false) {
+                // Append everything that is before the text to be decoded
+                $out .= substr($input, 0, $pos);
 
-        // Get the location of the text to decode
-        $end_cs_pos = strpos($input, "?", $pos+2);
-        $end_en_pos = strpos($input, "?", $end_cs_pos+1);
-        $end_pos = strpos($input, "?=", $end_en_pos+1);
+                // Get the location of the text to decode
+                $end_cs_pos = strpos($input, "?", $pos+2);
+                $end_en_pos = strpos($input, "?", $end_cs_pos+1);
+                $end_pos = strpos($input, "?=", $end_en_pos+1);
 
-        // Extract the encoded string
-        $encstr = substr($input, $pos+2, ($end_pos-$pos-2));
-        // Extract the remaining string
-        $input = substr($input, $end_pos+2);
+                // Extract the encoded string
+                $encstr = substr($input, $pos+2, ($end_pos-$pos-2));
+                // Extract the remaining string
+                $input = substr($input, $end_pos+2);
 
-        // Decode the string fragement
-        $out .= rcube_imap::_decode_mime_string_part($encstr);
-      }
+                // Decode the string fragement
+                $out .= rcube_imap::_decode_mime_string_part($encstr);
+            }
 
-      // Deocde the rest (if any)
-      if (strlen($input) != 0)
-         $out .= rcube_imap::decode_mime_string($input, $fallback);
+            // Deocde the rest (if any)
+            if (strlen($input) != 0)
+                $out .= rcube_imap::decode_mime_string($input, $fallback);
 
-       // return the results
-      return $out;
-    }
+            // return the results
+            return $out;
+        }
 
-    // no encoding information, use fallback
-    return rcube_charset_convert($input, 
-      !empty($fallback) ? $fallback : rcmail::get_instance()->config->get('default_charset', 'ISO-8859-1'));
+        // no encoding information, use fallback
+        return rcube_charset_convert($input, 
+            !empty($fallback) ? $fallback : rcmail::get_instance()->config->get('default_charset', 'ISO-8859-1'));
     }
 
 
-  /**
-   * Decode a part of a mime-encoded string
-   *
-   * @access private
-   */
-  private function _decode_mime_string_part($str)
+    /**
+     * Decode a part of a mime-encoded string
+     *
+     * @access private
+     */
+    private function _decode_mime_string_part($str)
     {
-    $a = explode('?', $str);
-    $count = count($a);
+        $a = explode('?', $str);
+        $count = count($a);
 
-    // should be in format "charset?encoding?base64_string"
-    if ($count >= 3)
-      {
-      for ($i=2; $i<$count; $i++)
-        $rest.=$a[$i];
+        // should be in format "charset?encoding?base64_string"
+        if ($count >= 3) {
+            for ($i=2; $i<$count; $i++)
+                $rest .= $a[$i];
 
-      if (($a[1]=="B")||($a[1]=="b"))
-        $rest = base64_decode($rest);
-      else if (($a[1]=="Q")||($a[1]=="q"))
-        {
-        $rest = str_replace("_", " ", $rest);
-        $rest = quoted_printable_decode($rest);
+            if (($a[1]=='B') || ($a[1]=='b'))
+                $rest = base64_decode($rest);
+            else if (($a[1]=='Q') || ($a[1]=='q')) {
+                $rest = str_replace('_', ' ', $rest);
+                $rest = quoted_printable_decode($rest);
+            }
+
+            return rcube_charset_convert($rest, $a[0]);
         }
 
-      return rcube_charset_convert($rest, $a[0]);
-      }
-    else
-      return $str;    // we dont' know what to do with this  
+        // we dont' know what to do with this  
+        return $str;
+    }
+
+
+    /**
+     * Decode a mime part
+     *
+     * @param string Input string
+     * @param string Part encoding
+     * @return string Decoded string
+     */
+    function mime_decode($input, $encoding='7bit')
+    {
+        switch (strtolower($encoding)) {
+        case 'quoted-printable':
+            return quoted_printable_decode($input);
+        case 'base64':
+            return base64_decode($input);
+        case 'x-uuencode':
+        case 'x-uue':
+        case 'uue':
+        case 'uuencode':
+            return convert_uudecode($input);
+        case '7bit':
+        default:
+            return $input;
+        }
     }
 
 
-  /**
-   * Decode a mime part
-   *
-   * @param string Input string
-   * @param string Part encoding
-   * @return string Decoded string
-   */
-  function mime_decode($input, $encoding='7bit')
+    /**
+     * Convert body charset to RCMAIL_CHARSET according to the ctype_parameters
+     *
+     * @param string Part body to decode
+     * @param string Charset to convert from
+     * @return string Content converted to internal charset
+     */
+    function charset_decode($body, $ctype_param)
     {
-    switch (strtolower($encoding))
-      {
-      case 'quoted-printable':
-        return quoted_printable_decode($input);
-        break;
-      
-      case 'base64':
-        return base64_decode($input);
-        break;
-
-      case 'x-uuencode':
-      case 'x-uue':
-      case 'uue':
-      case 'uuencode':
-        return convert_uudecode($input);
-        break;
-						      
-      case '7bit':
-      default:
-        return $input;
-      }
-    }
-
+        if (is_array($ctype_param) && !empty($ctype_param['charset']))
+            return rcube_charset_convert($body, $ctype_param['charset']);
 
-  /**
-   * Convert body charset to RCMAIL_CHARSET according to the ctype_parameters
-   *
-   * @param string Part body to decode
-   * @param string Charset to convert from
-   * @return string Content converted to internal charset
-   */
-  function charset_decode($body, $ctype_param)
-    {
-    if (is_array($ctype_param) && !empty($ctype_param['charset']))
-      return rcube_charset_convert($body, $ctype_param['charset']);
-
-    // defaults to what is specified in the class header
-    return rcube_charset_convert($body,  $this->default_charset);
-    }
-
-
-  /**
-   * Translate UID to message ID
-   *
-   * @param int    Message UID
-   * @param string Mailbox name
-   * @return int   Message ID
-   */
-  function get_id($uid, $mbox_name=NULL) 
-    {
-      $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
-      return $this->_uid2id($uid, $mailbox);
-    }
-
-
-  /**
-   * Translate message number to UID
-   *
-   * @param int    Message ID
-   * @param string Mailbox name
-   * @return int   Message UID
-   */
-  function get_uid($id,$mbox_name=NULL)
-    {
-      $mailbox = $mbox_name ? $this->mod_mailbox($mbox_name) : $this->mailbox;
-      return $this->_id2uid($id, $mailbox);
+        // defaults to what is specified in the class header
+        return rcube_charset_convert($body,  $this->default_charset);
     }
 
 
-  /**
-   * Modify folder name for input/output according to root dir and namespace
-   *
-   * @param string  Folder name
-   * @param string  Mode
-   * @return string Folder name
-   */
-  function mod_mailbox($mbox_name, $mode='in')
-    {
-    if ($mbox_name == 'INBOX')
-      return $mbox_name;
-
-    if (!empty($this->root_dir)) {
-      if ($mode=='in')
-        $mbox_name = $this->root_dir.$this->delimiter.$mbox_name;
-      else if (!empty($mbox_name)) // $mode=='out'
-        $mbox_name = substr($mbox_name, strlen($this->root_dir)+1);
-      }
-    
-    return $mbox_name;
-    }
-
-
-  /* --------------------------------
-   *         private methods
-   * --------------------------------*/
-
-  /**
-   * Validate the given input and save to local properties
-   * @access private
-   */
-  private function _set_sort_order($sort_field, $sort_order)
-  {
-    if ($sort_field != null)
-      $this->sort_field = asciiwords($sort_field);
-    if ($sort_order != null)
-      $this->sort_order = strtoupper($sort_order) == 'DESC' ? 'DESC' : 'ASC';
-  }
+    /* --------------------------------
+     *         private methods
+     * --------------------------------*/
 
-  /**
-   * Sort mailboxes first by default folders and then in alphabethical order
-   * @access private
-   */
-  private function _sort_mailbox_list($a_folders)
+    /**
+     * Validate the given input and save to local properties
+     * @access private
+     */
+    private function _set_sort_order($sort_field, $sort_order)
     {
-    $a_out = $a_defaults = $folders = array();
+        if ($sort_field != null)
+            $this->sort_field = asciiwords($sort_field);
+        if ($sort_order != null)
+            $this->sort_order = strtoupper($sort_order) == 'DESC' ? 'DESC' : 'ASC';
+    }
 
-    $delimiter = $this->get_hierarchy_delimiter();
+    /**
+     * Sort mailboxes first by default folders and then in alphabethical order
+     * @access private
+     */
+    private function _sort_mailbox_list($a_folders)
+    {
+        $a_out = $a_defaults = $folders = array();
 
-    // find default folders and skip folders starting with '.'
-    foreach ($a_folders as $i => $folder)
-      {
-      if ($folder{0}=='.')
-        continue;
+        $delimiter = $this->get_hierarchy_delimiter();
 
-      if (($p = array_search($folder, $this->default_folders)) !== false && !$a_defaults[$p])
-        $a_defaults[$p] = $folder;
-      else
-        $folders[$folder] = mb_strtolower(rcube_charset_convert($folder, 'UTF7-IMAP'));
-      }
+        // find default folders and skip folders starting with '.'
+        foreach ($a_folders as $i => $folder) {
+            if ($folder[0] == '.')
+                continue;
 
-    // sort folders and place defaults on the top
-    asort($folders, SORT_LOCALE_STRING);
-    ksort($a_defaults);
-    $folders = array_merge($a_defaults, array_keys($folders));
+            if (($p = array_search($folder, $this->default_folders)) !== false && !$a_defaults[$p])
+                $a_defaults[$p] = $folder;
+            else
+                $folders[$folder] = mb_strtolower(rcube_charset_convert($folder, 'UTF7-IMAP'));
+        }
 
-    // finally we must rebuild the list to move 
-    // subfolders of default folders to their place...
-    // ...also do this for the rest of folders because
-    // asort() is not properly sorting case sensitive names
-    while (list($key, $folder) = each($folders)) {
-      // set the type of folder name variable (#1485527) 
-      $a_out[] = (string) $folder;
-      unset($folders[$key]);
-      $this->_rsort($folder, $delimiter, $folders, $a_out);	
-      }
+        // sort folders and place defaults on the top
+        asort($folders, SORT_LOCALE_STRING);
+        ksort($a_defaults);
+        $folders = array_merge($a_defaults, array_keys($folders));
+
+        // finally we must rebuild the list to move 
+        // subfolders of default folders to their place...
+        // ...also do this for the rest of folders because
+        // asort() is not properly sorting case sensitive names
+        while (list($key, $folder) = each($folders)) {
+            // set the type of folder name variable (#1485527) 
+            $a_out[] = (string) $folder;
+            unset($folders[$key]);
+            $this->_rsort($folder, $delimiter, $folders, $a_out);	
+        }
 
-    return $a_out;
+        return $a_out;
     }
 
 
-  /**
-   * @access private
-   */
-  private function _rsort($folder, $delimiter, &$list, &$out)
-    {
-      while (list($key, $name) = each($list)) {
-	if (strpos($name, $folder.$delimiter) === 0) {
-	  // set the type of folder name variable (#1485527) 
-    	  $out[] = (string) $name;
-	  unset($list[$key]);
-	  $this->_rsort($name, $delimiter, $list, $out);
-	  }
+    /**
+     * @access private
+     */
+    private function _rsort($folder, $delimiter, &$list, &$out)
+    {
+        while (list($key, $name) = each($list)) {
+	        if (strpos($name, $folder.$delimiter) === 0) {
+	            // set the type of folder name variable (#1485527) 
+    	        $out[] = (string) $name;
+	            unset($list[$key]);
+	            $this->_rsort($name, $delimiter, $list, $out);
+	        }
         }
-      reset($list);	
+        reset($list);	
     }
 
 
-  /**
-   * @access private
-   */
-  private function _uid2id($uid, $mbox_name=NULL)
-    {
-    if (!$mbox_name)
-      $mbox_name = $this->mailbox;
+    /**
+     * @access private
+     */
+    private function _uid2id($uid, $mbox_name=NULL)
+    {
+        if (!$mbox_name)
+            $mbox_name = $this->mailbox;
       
-    if (!isset($this->uid_id_map[$mbox_name][$uid]))
-      $this->uid_id_map[$mbox_name][$uid] = iil_C_UID2ID($this->conn, $mbox_name, $uid);
+        if (!isset($this->uid_id_map[$mbox_name][$uid]))
+            $this->uid_id_map[$mbox_name][$uid] = $this->conn->UID2ID($mbox_name, $uid);
 
-    return $this->uid_id_map[$mbox_name][$uid];
+        return $this->uid_id_map[$mbox_name][$uid];
     }
 
-  /**
-   * @access private
-   */
-  private function _id2uid($id, $mbox_name=NULL)
+    /**
+     * @access private
+     */
+    private function _id2uid($id, $mbox_name=NULL)
     {
-    if (!$mbox_name)
-      $mbox_name = $this->mailbox;
+        if (!$mbox_name)
+            $mbox_name = $this->mailbox;
 
-    if ($uid = array_search($id, (array)$this->uid_id_map[$mbox_name]))
-      return $uid;
+        if ($uid = array_search($id, (array)$this->uid_id_map[$mbox_name]))
+            return $uid;
 
-    $uid = iil_C_ID2UID($this->conn, $mbox_name, $id);
-    $this->uid_id_map[$mbox_name][$uid] = $id;
+        $uid = $this->conn->ID2UID($mbox_name, $id);
+        $this->uid_id_map[$mbox_name][$uid] = $id;
     
-    return $uid;
+        return $uid;
     }
 
 
-  /**
-   * Subscribe/unsubscribe a list of mailboxes and update local cache
-   * @access private
-   */
-  private function _change_subscription($a_mboxes, $mode)
+    /**
+     * Subscribe/unsubscribe a list of mailboxes and update local cache
+     * @access private
+     */
+    private function _change_subscription($a_mboxes, $mode)
     {
-    $updated = false;
+        $updated = false;
 
-    if (is_array($a_mboxes))
-      foreach ($a_mboxes as $i => $mbox_name)
-        {
-        $mailbox = $this->mod_mailbox($mbox_name);
-        $a_mboxes[$i] = $mailbox;
+        if (is_array($a_mboxes))
+            foreach ($a_mboxes as $i => $mbox_name) {
+                $mailbox = $this->mod_mailbox($mbox_name);
+                $a_mboxes[$i] = $mailbox;
 
-        if ($mode=='subscribe')
-          $updated = iil_C_Subscribe($this->conn, $mailbox);
-        else if ($mode=='unsubscribe')
-          $updated = iil_C_UnSubscribe($this->conn, $mailbox);
-        }
+                if ($mode=='subscribe')
+                    $updated = $this->conn->subscribe($mailbox);
+                else if ($mode=='unsubscribe')
+                    $updated = $this->conn->unsubscribe($mailbox);
+            }
 
-    // get cached mailbox list
-    if ($updated)
-      {
-      $a_mailbox_cache = $this->get_cache('mailboxes');
-      if (!is_array($a_mailbox_cache))
-        return $updated;
+        // get cached mailbox list
+        if ($updated) {
+            $a_mailbox_cache = $this->get_cache('mailboxes');
+            if (!is_array($a_mailbox_cache))
+                return $updated;
 
-      // modify cached list
-      if ($mode=='subscribe')
-        $a_mailbox_cache = array_merge($a_mailbox_cache, $a_mboxes);
-      else if ($mode=='unsubscribe')
-        $a_mailbox_cache = array_diff($a_mailbox_cache, $a_mboxes);
+            // modify cached list
+            if ($mode=='subscribe')
+                $a_mailbox_cache = array_merge($a_mailbox_cache, $a_mboxes);
+            else if ($mode=='unsubscribe')
+                $a_mailbox_cache = array_diff($a_mailbox_cache, $a_mboxes);
 
-      // write mailboxlist to cache
-      $this->update_cache('mailboxes', $this->_sort_mailbox_list($a_mailbox_cache));
-      }
+            // write mailboxlist to cache
+            $this->update_cache('mailboxes', $this->_sort_mailbox_list($a_mailbox_cache));
+        }
 
-    return $updated;
+        return $updated;
     }
 
 
-  /**
-   * Increde/decrese messagecount for a specific mailbox
-   * @access private
-   */
-  private function _set_messagecount($mbox_name, $mode, $increment)
+    /**
+     * Increde/decrese messagecount for a specific mailbox
+     * @access private
+     */
+    private function _set_messagecount($mbox_name, $mode, $increment)
     {
-    $a_mailbox_cache = false;
-    $mailbox = $mbox_name ? $mbox_name : $this->mailbox;
-    $mode = strtoupper($mode);
+        $a_mailbox_cache = false;
+        $mailbox = $mbox_name ? $mbox_name : $this->mailbox;
+        $mode = strtoupper($mode);
 
-    $a_mailbox_cache = $this->get_cache('messagecount');
+        $a_mailbox_cache = $this->get_cache('messagecount');
     
-    if (!is_array($a_mailbox_cache[$mailbox]) || !isset($a_mailbox_cache[$mailbox][$mode]) || !is_numeric($increment))
-      return false;
+        if (!is_array($a_mailbox_cache[$mailbox]) || !isset($a_mailbox_cache[$mailbox][$mode]) || !is_numeric($increment))
+            return false;
     
-    // add incremental value to messagecount
-    $a_mailbox_cache[$mailbox][$mode] += $increment;
+        // add incremental value to messagecount
+        $a_mailbox_cache[$mailbox][$mode] += $increment;
     
-    // there's something wrong, delete from cache
-    if ($a_mailbox_cache[$mailbox][$mode] < 0)
-      unset($a_mailbox_cache[$mailbox][$mode]);
+        // there's something wrong, delete from cache
+        if ($a_mailbox_cache[$mailbox][$mode] < 0)
+            unset($a_mailbox_cache[$mailbox][$mode]);
 
-    // write back to cache
-    $this->update_cache('messagecount', $a_mailbox_cache);
+        // write back to cache
+        $this->update_cache('messagecount', $a_mailbox_cache);
     
-    return true;
+        return true;
     }
 
 
-  /**
-   * Remove messagecount of a specific mailbox from cache
-   * @access private
-   */
-  private function _clear_messagecount($mbox_name='')
+    /**
+     * Remove messagecount of a specific mailbox from cache
+     * @access private
+     */
+    private function _clear_messagecount($mbox_name='')
     {
-    $a_mailbox_cache = false;
-    $mailbox = $mbox_name ? $mbox_name : $this->mailbox;
+        $a_mailbox_cache = false;
+        $mailbox = $mbox_name ? $mbox_name : $this->mailbox;
 
-    $a_mailbox_cache = $this->get_cache('messagecount');
+        $a_mailbox_cache = $this->get_cache('messagecount');
 
-    if (is_array($a_mailbox_cache[$mailbox]))
-      {
-      unset($a_mailbox_cache[$mailbox]);
-      $this->update_cache('messagecount', $a_mailbox_cache);
-      }
+        if (is_array($a_mailbox_cache[$mailbox])) {
+            unset($a_mailbox_cache[$mailbox]);
+            $this->update_cache('messagecount', $a_mailbox_cache);
+        }
     }
 
 
-  /**
-   * Split RFC822 header string into an associative array
-   * @access private
-   */
-  private function _parse_headers($headers)
+    /**
+     * Split RFC822 header string into an associative array
+     * @access private
+     */
+    private function _parse_headers($headers)
     {
-    $a_headers = array();
-    $headers = preg_replace('/\r?\n(\t| )+/', ' ', $headers);
-    $lines = explode("\n", $headers);
-    $c = count($lines);
-    for ($i=0; $i<$c; $i++)
-      {
-      if ($p = strpos($lines[$i], ': '))
-        {
-        $field = strtolower(substr($lines[$i], 0, $p));
-        $value = trim(substr($lines[$i], $p+1));
-        if (!empty($value))
-          $a_headers[$field] = $value;
+        $a_headers = array();
+        $headers = preg_replace('/\r?\n(\t| )+/', ' ', $headers);
+        $lines = explode("\n", $headers);
+        $c = count($lines);
+
+        for ($i=0; $i<$c; $i++) {
+            if ($p = strpos($lines[$i], ': ')) {
+                $field = strtolower(substr($lines[$i], 0, $p));
+                $value = trim(substr($lines[$i], $p+1));
+                if (!empty($value))
+                    $a_headers[$field] = $value;
+            }
         }
-      }
     
-    return $a_headers;
+        return $a_headers;
     }
 
 
-  /**
-   * @access private
-   */
-  private function _parse_address_list($str, $decode=true)
+    /**
+     * @access private
+     */
+    private function _parse_address_list($str, $decode=true)
     {
-    // remove any newlines and carriage returns before
-    $a = rcube_explode_quoted_string('[,;]', preg_replace( "/[\r\n]/", " ", $str));
-    $result = array();
+        // remove any newlines and carriage returns before
+        $a = rcube_explode_quoted_string('[,;]', preg_replace( "/[\r\n]/", " ", $str));
+        $result = array();
 
-    foreach ($a as $key => $val)
-      {
-      $val = preg_replace("/([\"\w])</", "$1 <", $val);
-      $sub_a = rcube_explode_quoted_string(' ', $decode ? $this->decode_header($val) : $val);
-      $result[$key]['name'] = '';
+        foreach ($a as $key => $val) {
+            $val = preg_replace("/([\"\w])</", "$1 <", $val);
+            $sub_a = rcube_explode_quoted_string(' ', $decode ? $this->decode_header($val) : $val);
+            $result[$key]['name'] = '';
 
-      foreach ($sub_a as $k => $v)
-        {
-	// use angle brackets in regexp to not handle names with @ sign
-        if (preg_match('/^<\S+@\S+>$/', $v))
-          $result[$key]['address'] = trim($v, '<>');
-        else
-          $result[$key]['name'] .= (empty($result[$key]['name'])?'':' ').str_replace("\"",'',stripslashes($v));
-        }
+            foreach ($sub_a as $k => $v) {
+	            // use angle brackets in regexp to not handle names with @ sign
+                if (preg_match('/^<\S+@\S+>$/', $v))
+                    $result[$key]['address'] = trim($v, '<>');
+                else
+                    $result[$key]['name'] .= (empty($result[$key]['name'])?'':' ').str_replace("\"",'',stripslashes($v));
+            }
         
-      if (empty($result[$key]['name']))
-        $result[$key]['name'] = $result[$key]['address'];        
-      elseif (empty($result[$key]['address']))
-        $result[$key]['address'] = $result[$key]['name'];
-      }
+            if (empty($result[$key]['name']))
+                $result[$key]['name'] = $result[$key]['address'];        
+            elseif (empty($result[$key]['address']))
+                $result[$key]['address'] = $result[$key]['name'];
+        }
     
-    return $result;
+        return $result;
     }
 
 }  // end class rcube_imap
@@ -3768,80 +3734,80 @@ class rcube_imap
  */
 class rcube_message_part
 {
-  var $mime_id = '';
-  var $ctype_primary = 'text';
-  var $ctype_secondary = 'plain';
-  var $mimetype = 'text/plain';
-  var $disposition = '';
-  var $filename = '';
-  var $encoding = '8bit';
-  var $charset = '';
-  var $size = 0;
-  var $headers = array();
-  var $d_parameters = array();
-  var $ctype_parameters = array();
-
-  function __clone()
-  {
-    if (isset($this->parts))
-      foreach ($this->parts as $idx => $part)
-        if (is_object($part))
-	  $this->parts[$idx] = clone $part;
-  }				
+    var $mime_id = '';
+    var $ctype_primary = 'text';
+    var $ctype_secondary = 'plain';
+    var $mimetype = 'text/plain';
+    var $disposition = '';
+    var $filename = '';
+    var $encoding = '8bit';
+    var $charset = '';
+    var $size = 0;
+    var $headers = array();
+    var $d_parameters = array();
+    var $ctype_parameters = array();
+
+    function __clone()
+    {
+        if (isset($this->parts))
+            foreach ($this->parts as $idx => $part)
+                if (is_object($part))
+	                $this->parts[$idx] = clone $part;
+    }
 }
 
 
 /**
- * Class for sorting an array of iilBasicHeader objects in a predetermined order.
+ * Class for sorting an array of rcube_mail_header objects in a predetermined order.
  *
  * @package Mail
  * @author Eric Stadtherr
  */
 class rcube_header_sorter
 {
-   var $sequence_numbers = array();
+    var $sequence_numbers = array();
    
-   /**
-    * Set the predetermined sort order.
-    *
-    * @param array Numerically indexed array of IMAP message sequence numbers
-    */
-   function set_sequence_numbers($seqnums)
-   {
-      $this->sequence_numbers = array_flip($seqnums);
-   }
- 
-   /**
-    * Sort the array of header objects
-    *
-    * @param array Array of iilBasicHeader objects indexed by UID
-    */
-   function sort_headers(&$headers)
-   {
-      /*
-       * uksort would work if the keys were the sequence number, but unfortunately
-       * the keys are the UIDs.  We'll use uasort instead and dereference the value
-       * to get the sequence number (in the "id" field).
-       * 
-       * uksort($headers, array($this, "compare_seqnums")); 
-       */
-       uasort($headers, array($this, "compare_seqnums"));
-   }
+    /**
+     * Set the predetermined sort order.
+     *
+     * @param array Numerically indexed array of IMAP message sequence numbers
+     */
+    function set_sequence_numbers($seqnums)
+    {
+        $this->sequence_numbers = array_flip($seqnums);
+    }
+
+    /**
+     * Sort the array of header objects
+     *
+     * @param array Array of rcube_mail_header objects indexed by UID
+     */
+    function sort_headers(&$headers)
+    {
+        /*
+        * uksort would work if the keys were the sequence number, but unfortunately
+        * the keys are the UIDs.  We'll use uasort instead and dereference the value
+        * to get the sequence number (in the "id" field).
+        * 
+        * uksort($headers, array($this, "compare_seqnums")); 
+        */
+        uasort($headers, array($this, "compare_seqnums"));
+    }
  
-   /**
-    * Sort method called by uasort()
-    */
-   function compare_seqnums($a, $b)
-   {
-      // First get the sequence number from the header object (the 'id' field).
-      $seqa = $a->id;
-      $seqb = $b->id;
+    /**
+     * Sort method called by uasort()
+     */
+    function compare_seqnums($a, $b)
+    {
+        // First get the sequence number from the header object (the 'id' field).
+        $seqa = $a->id;
+        $seqb = $b->id;
       
-      // then find each sequence number in my ordered list
-      $posa = isset($this->sequence_numbers[$seqa]) ? intval($this->sequence_numbers[$seqa]) : -1;
-      $posb = isset($this->sequence_numbers[$seqb]) ? intval($this->sequence_numbers[$seqb]) : -1;
+        // then find each sequence number in my ordered list
+        $posa = isset($this->sequence_numbers[$seqa]) ? intval($this->sequence_numbers[$seqa]) : -1;
+        $posb = isset($this->sequence_numbers[$seqb]) ? intval($this->sequence_numbers[$seqb]) : -1;
       
-      // return the relative position as the comparison value
-      return $posa - $posb;
-   }
+        // return the relative position as the comparison value
+        return $posa - $posb;
+    }
 }