diff --git a/api/src/CalDAV.php b/api/src/CalDAV.php
index 2db20626cc..7036530b7a 100644
--- a/api/src/CalDAV.php
+++ b/api/src/CalDAV.php
@@ -393,6 +393,7 @@ class CalDAV extends HTTP_WebDAV_Server
 					'location' => 'groupdav_root_props',
 					'props' => &$files['files'][0]['props'],
 					'options' => $options,
+					'caldav' => $this,
 				));
 			}