Index: roundcubemail/program/steps/mail/func.inc
===================================================================
--- roundcubemail/program/steps/mail/func.inc	(revision 2308)
+++ roundcubemail/program/steps/mail/func.inc	(working copy)
@@ -80,7 +80,7 @@
       }
     
       // make sure the message count is refreshed (for default view)
-      $IMAP->messagecount($mbox_name, 'ALL', true);
+      $IMAP->messagecount($mbox_name,rcmail::get_instance()->config->get('message_threading',false)?'THREADS':'ALL', true);
     }
 	
   // set current mailbox in client environment
@@ -152,7 +152,6 @@
   
   // add col definition
   $out .= '<colgroup>';
-  $out .= '<col class="icon" />';
 
   foreach ($a_show_cols as $col)
     $out .= ($col!='attachment') ? sprintf('<col class="%s" />', $col) : '<col class="icon" />';
@@ -160,7 +159,7 @@
   $out .= "</colgroup>\n";
 
   // add table title
-  $out .= "<thead><tr>\n<td class=\"icon\">&nbsp;</td>\n";
+  $out .= "<thead><tr>\n";
 
   $javascript = '';
   foreach ($a_show_cols as $col)
@@ -257,6 +256,9 @@
       $js_row_arr['forwarded'] = true;
     if ($header->flagged)
       $js_row_arr['flagged'] = true;
+    if ($header->has_children)
+      $js_row_arr['has_children'] = true;
+    $js_row_arr['depth'] = $header->depth;
 
     // set message icon  
     if ($attrib['deletedicon'] && $header->deleted)
@@ -284,19 +286,28 @@
     if ($attrib['attachmenticon'] && preg_match("/multipart\/m/i", $header->ctype))
       $attach_icon = $attrib['attachmenticon'];
         
-    $out .= sprintf('<tr id="rcmrow%d" class="message%s%s%s%s">'."\n",
+    $out .= sprintf('<tr id="rcmrow%d" class="message%s%s%s%s"%s>'."\n",
                     $header->uid,
                     $header->seen ? '' : ' unread',
                     $header->deleted ? ' deleted' : '',
                     $header->flagged ? ' flagged' : '',
-                    $zebra_class);
+                    $zebra_class,
+                    ($header->depth  > 1) ? ' style="display: none"' : '');
     
-    $out .= sprintf("<td class=\"icon\">%s</td>\n", $message_icon ? sprintf($image_tag, $skin_path, $message_icon, '') : '');
+    $tree = '';
+    $depth = $header->depth;
+    if ($depth > 0)
+      {
+      for ($i=1;$i<$depth;$i++)
+        $tree .= '<div class="branch">&nbsp</div>';
+      $tree .= $header->has_children?'<div id="rcmexpando' . $header->uid . '" class="collapsed">&nbsp;</div>':'<div class="leaf">&nbsp;</div>';
+      }
+    $tree .= $message_icon ? sprintf($image_tag, $skin_path, $message_icon, '') : '';
 
-
     $IMAP->set_charset(!empty($header->charset) ? $header->charset : $CONFIG['default_charset']);
   
     // format each col
+    $first = true;
     foreach ($a_show_cols as $col)
       {
       if ($col=='from' || $col=='to')
@@ -318,6 +329,10 @@
       else
         $cont = Q($header->$col);
         
+      if ($first) {
+      	$first = false;
+      	$cont = $tree . $cont;
+      }
       if ($col!='attachment')
         $out .= '<td class="'.$col.'">' . $cont . "</td>\n";
       else
@@ -333,7 +348,7 @@
   // complete message table
   $out .= "</tbody></table>\n";
   
-  $message_count = $IMAP->messagecount();
+  $message_count = $IMAP->messagecount(NULL, rcmail::get_instance()->config->get('message_threading',false)?'THREADS':'ALL');
   
   // set client env
   $OUTPUT->add_gui_object('mailcontframe', 'mailcontframe');
@@ -393,6 +408,12 @@
 
   $OUTPUT->command('set_message_coltypes', $a_show_cols);
 
+  // remove 'attachment' and 'flag' columns, we don't need them here
+  if(($key = array_search('attachment', $a_show_cols)) !== FALSE)
+    unset($a_show_cols[$key]);
+  if(($key = array_search('flag', $a_show_cols)) !== FALSE)
+    unset($a_show_cols[$key]);
+
   // loop through message headers
   foreach ($a_headers as $n => $header)
     {
@@ -404,12 +425,6 @@
 
     $IMAP->set_charset(!empty($header->charset) ? $header->charset : $CONFIG['default_charset']);
 
-    // remove 'attachment' and 'flag' columns, we don't need them here
-    if(($key = array_search('attachment', $a_show_cols)) !== FALSE)
-      unset($a_show_cols[$key]);
-    if(($key = array_search('flag', $a_show_cols)) !== FALSE)
-      unset($a_show_cols[$key]);
-
     // format each col; similar as in rcmail_message_list()
     foreach ($a_show_cols as $col)
       {
@@ -438,6 +453,8 @@
     $a_msg_flags['replied'] = $header->answered ? 1 : 0;
     $a_msg_flags['forwarded'] = $header->forwarded ? 1 : 0;
     $a_msg_flags['flagged'] = $header->flagged ? 1 : 0;
+    $a_msg_flags['has_children'] = $header->has_children ? 1 : 0;
+    $a_msg_cols['depth'] = $header->depth;
     
     $OUTPUT->command('add_message_row',
       $header->uid,
@@ -446,6 +463,7 @@
       preg_match("/multipart\/m/i", $header->ctype),
       $insert_top);
     }
+  $OUTPUT->command('expand_threads');
   }
 
 
@@ -565,23 +583,24 @@
   {
   global $IMAP, $MESSAGE;
   
+  $message_threading = rcmail::get_instance()->config->get('message_threading',false);
   if (isset($MESSAGE->index))
     {
     return rcube_label(array('name' => 'messagenrof',
                              'vars' => array('nr'  => $MESSAGE->index+1,
-                                             'count' => $count!==NULL ? $count : $IMAP->messagecount())));
+                                             'count' => $count!==NULL ? $count : $IMAP->messagecount(NULL, $message_threading?'THREADS':'ALL'))));
     }
 
   if ($page===NULL)
     $page = $IMAP->list_page;
     
   $start_msg = ($page-1) * $IMAP->page_size + 1;
-  $max = $count!==NULL ? $count : $IMAP->messagecount();
+  $max = $count!==NULL ? $count : $IMAP->messagecount(NULL, $message_threading?'THREADS':'ALL');
 
   if ($max==0)
     $out = rcube_label('mailboxempty');
   else
-    $out = rcube_label(array('name' => 'messagesfromto',
+    $out = rcube_label(array('name' => $message_threading?'threadsfromto':'messagesfromto',
                               'vars' => array('from'  => $start_msg,
                                               'to'    => min($max, $start_msg + $IMAP->page_size - 1),
                                               'count' => $max)));