diff --git a/plugins/calendar/drivers/kolab/kolab_calendar.php b/plugins/calendar/drivers/kolab/kolab_calendar.php
index c2901e42..23915465 100644
--- a/plugins/calendar/drivers/kolab/kolab_calendar.php
+++ b/plugins/calendar/drivers/kolab/kolab_calendar.php
@@ -15,7 +15,7 @@
  +-------------------------------------------------------------------------+
 */
 
-class Kolab_calendar
+class kolab_calendar
 {
   public $id;
   public $ready = false;