diff --git a/plugins/tasklist/drivers/kolab/tasklist_kolab_driver.php b/plugins/tasklist/drivers/kolab/tasklist_kolab_driver.php
index 8ba59dec..9000d8fb 100644
--- a/plugins/tasklist/drivers/kolab/tasklist_kolab_driver.php
+++ b/plugins/tasklist/drivers/kolab/tasklist_kolab_driver.php
@@ -717,8 +717,9 @@ class tasklist_kolab_driver extends tasklist_driver
             $format->get_attachments($rec, true);
 
             if ($format->is_valid()) {
+                $rec = self::_to_rcube_task($rec, $list_id, false);
                 $rec['rev'] = $result['rev'];
-                return self::_to_rcube_task($rec, $list_id, false);
+                return $rec;
             }
         }
 
diff --git a/plugins/tasklist/tasklist.js b/plugins/tasklist/tasklist.js
index 514d0602..d31a26d7 100644
--- a/plugins/tasklist/tasklist.js
+++ b/plugins/tasklist/tasklist.js
@@ -2575,7 +2575,7 @@ function rcube_tasklist_ui(settings)
 
         var query = { _id: att.id, _t: rec.recurrence_id||rec.id, _list:rec.list, _frame: 1 };
         if (rec.rev)
-            query._rev = event.rev;
+            query._rev = rec.rev;
 
 
         // open attachment in frame if it's of a supported mimetype