diff --git a/plugins/kolab_chat/drivers/mattermost.php b/plugins/kolab_chat/drivers/mattermost.php
index abf1c530..f9bb8b29 100644
--- a/plugins/kolab_chat/drivers/mattermost.php
+++ b/plugins/kolab_chat/drivers/mattermost.php
@@ -55,10 +55,16 @@ class kolab_chat_mattermost
             $url .= '/api/v4/websocket';
         }
         else if ($this->rc->action == 'index' && $this->rc->task == 'kolab-chat') {
-            if (($channel = rcube_utils::get_input_value('_channel', rcube_utils::INPUT_GET))
-                && ($channel = $this->get_channel($channel, true))
-            ) {
-                $url .= '/' . urlencode($channel['team_name']) . '/channels/' . urlencode($channel['id']);
+            if ($channel = rcube_utils::get_input_value('_channel', rcube_utils::INPUT_GET)) {
+                $team    = rcube_utils::get_input_value('_team', rcube_utils::INPUT_GET);
+
+                if (empty($team) && ($_channel = $this->get_channel($channel, true))) {
+                    $team = $_channel['team_name'];
+                }
+
+                if ($channel && $team) {
+                    $url .= '/' . urlencode($team) . '/channels/' . urlencode($channel);
+                }
             }
         }
 
@@ -72,7 +78,7 @@ class kolab_chat_mattermost
     {
         if ($this->rc->task != 'kolab-chat') {
             $this->plugin->include_script("js/mattermost.js");
-            $this->plugin->add_label('openchat', 'directmessage');
+            $this->plugin->add_label('openchat', 'directmessage', 'mentionmessage');
         }
         else if ($this->get_token()) {
             rcube_utils::setcookie('MMUSERID', $_SESSION['mattermost'][0], 0, false);
@@ -86,8 +92,9 @@ class kolab_chat_mattermost
     public function action()
     {
         $result = array(
-            'url'   => $this->url(true),
-            'token' => $this->get_token(),
+            'url'     => $this->url(true),
+            'token'   => $this->get_token(),
+            'user_id' => $this->get_user_id(),
         );
 
         echo rcube_output::json_serialize($result);
diff --git a/plugins/kolab_chat/js/mattermost.js b/plugins/kolab_chat/js/mattermost.js
index 23ff6b99..7bcc2fb5 100644
--- a/plugins/kolab_chat/js/mattermost.js
+++ b/plugins/kolab_chat/js/mattermost.js
@@ -278,23 +278,43 @@ function mattermost_websocket_init(url, token)
  */
 function mattermost_event_handler(event)
 {
-    // We're interested only in direct messages for now
+    var msg, type;
+
+    // Direct message notification
     if (event.event == 'posted' && event.data.channel_type == 'D') {
-        var user = event.data.sender_name,
+        msg = rcmail.gettext('kolab_chat.directmessage');
+        type = 'user';
+    }
+    // Mention notification
+    else if (event.event == 'posted' && String(event.data.mentions).indexOf(rcmail.env.mattermost_user) > 0) {
+        msg = rcmail.gettext('kolab_chat.mentionmessage');
+        type = 'channel';
+    }
+
+    if (msg) {
+        var link = $('<a>').text(rcmail.gettext('kolab_chat.openchat')),
+            user = event.data.sender_name,
+            channel = event.data.channel_display_name,
             channel_id = event.broadcast.channel_id,
-            // channel_name = event.data.channel_display_name,
-            msg = rcmail.gettext('kolab_chat.directmessage').replace('$u', user),
-            link = $('<a>').text(rcmail.gettext('kolab_chat.openchat'))
-                .attr('href', '?_task=kolab-chat&_channel=' + urlencode(channel_id));
+            msg_id = 'chat-' + type + '-' + (type == 'channel' ? channel_id : user),
+            href = '?_task=kolab-chat&_channel=' + urlencode(channel_id);
+
+        msg = msg.replace('$u', user).replace('$c', channel);
 
         if (rcmail.env.kolab_chat_extwin) {
-            link.attr('target', '_blank').attr('href', link.attr('href') + '&redirect=1');
+            link.attr('target', '_blank');
+            href += '&redirect=1';
         }
 
+        if (event.data.team_id) {
+            href += '&_team=' + urlencode(event.data.team_id);
+        }
+
+        link.attr('href', href);
         msg = $('<p>').text(msg + ' ').append(link).html();
 
         // FIXME: Should we display it indefinitely?
-        rcmail.display_message(msg, 'notice chat', 10 * 60 * 1000, 'chat-user-' + user);
+        rcmail.display_message(msg, 'notice chat', 10 * 60 * 1000, msg_id);
     }
 }
 
@@ -307,7 +327,7 @@ window.WebSocket && window.rcmail && rcmail.addEventListener('init', function()
         success: function(data) {
             data = JSON.parse(data);
             if (data && data.token) {
-//                rcmail.set_env({mattermost_url: data.url, mattermost_token: data.token});
+                rcmail.set_env({mattermost_url: data.url, mattermost_token: data.token, mattermost_user: data.user_id});
                 mattermost_websocket_init(data.url, data.token);
             }
         }
diff --git a/plugins/kolab_chat/localization/en_US.inc b/plugins/kolab_chat/localization/en_US.inc
index 5561f2a9..7447e557 100644
--- a/plugins/kolab_chat/localization/en_US.inc
+++ b/plugins/kolab_chat/localization/en_US.inc
@@ -11,4 +11,5 @@
 $labels['chat'] = 'Chat';
 $labels['showinextwin'] = 'Open chat application in a new window';
 $labels['directmessage'] = 'A direct message from $u.';
+$labels['mentionmessage'] = 'You have been mentioned by $u in $c.';
 $labels['openchat'] = 'Open chat';