diff --git a/src/server/channel.py b/src/server/channel.py
index 2e89593..0c2dfa3 100644
--- a/src/server/channel.py
+++ b/src/server/channel.py
@@ -204,7 +204,7 @@ class ChannelTypeRoomList(Channel, _ChannelTypeRoomListIface):
         self._listing_rooms = False
         self._rooms = {}
 
-        self._add_immutables(self, {'Server': CHANNEL_TYPE_ROOM_LIST})
+        self._add_immutables({'Server': CHANNEL_TYPE_ROOM_LIST})
 
     @dbus.service.method(CHANNEL_TYPE_ROOM_LIST, in_signature='', out_signature='b')
     def GetListingRooms(self):