diff --git a/file/lib/data/chat/room/ChatRoom.class.php b/file/lib/data/chat/room/ChatRoom.class.php
index 1b8095b..e014ec4 100644
--- a/file/lib/data/chat/room/ChatRoom.class.php
+++ b/file/lib/data/chat/room/ChatRoom.class.php
@@ -1,6 +1,7 @@
 <?php
 namespace wcf\data\chat\room;
 use \wcf\system\cache\CacheHandler;
+use \wcf\system\WCF;
 
 /**
  * Represents a chat room.