Randall Kern writes:

.... Error Type: AttributeError Error Value: 'tuple' object has no attribute 'append' .... File /usr/src/Zope-2.2.2-src/lib/python/TreeDisplay/TreeTag.py, line 566, in apply_diff (Info: ([None, ([140975456, []],)], [140974880, 140974088])) AttributeError: (see above)

You may try to replace in "TreeDisplay.TreeTag.TreeTag.tpRender": if state is substate and not (args.has_key('single') and args['single']): state=state or ([id],) state=encode_seq(state) by: if state is substate and not (args.has_key('single') and args['single']): state=state or [[id],] state=encode_seq(state) If you do and have success, please file a bug report with patch into the collector. You may later get a different problem: In some contexts, the Zope security policy requires an acquisition context. You "Foo" objects do not have such contexts. If the problem shows up, you will get Unauthorized exceptions where you do not expect them. Dieter