Index: indico/MaKaC/rb_reservation.py
===================================================================
--- indico/MaKaC/rb_reservation.py	(revision c7361e65578f5bff81705cccdc6f49a216d3c04a)
+++ indico/MaKaC/rb_reservation.py	(revision 05de6f13d94b653bf02af46ab5cf28f30905f8a0)
@@ -1207,5 +1207,7 @@
         ####---ENDO OF FIXING THE USE OF IMPERSISTANT CLASS-----
         if self.__owner:
-            return ConferenceHolder().getById(self.__owner) #self.__owner.getObject() # Wrapped in Impersistant
+            ch = ConferenceHolder()
+            if ch.hasKey(self.__owner):
+                return ch.getById(self.__owner) #self.__owner.getObject() # Wrapped in Impersistant
 
         return None