I have installed the Zope 2.7.0 and have following problem: if I assign a proxy role to the constructor of a ZClass that was created automatically, and then try to add a new instance (for example, from the management screens) I get following error: (my ZClass name is Order2) Error Type: ValueError Error Value: unpack list of wrong size most recent traceback: Module None, line 3, in Order2_add <PythonScript at /Shop/Orders/SessionOrders/Order2_add> Line 3 Module AccessControl.Owned, line 127, in getWrappedOwner I tried to identify the problem, and I found out that getWrappedOwner returns an empty list, which causes the exception. But it seems that getWrappedOwner it is called at least two times, and the first call returns a proper value. Of course, in previous version, everything worked ok. If you have any ideas, I would be very grateful Marcin Wudarczyk http://mar.prv.pl