) Shane ___ Zope-Dev maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope-dev ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope )  Shane Hathaway wrote: My first recommendation would be to turn your ZClass registry into an OOBTree. OOBTree has been maintained and updated. Good thought, but no dice. Since it is rebuilding the registry on every restart anyway, I went ahead and made the changes to my OFS/Application.py. I confirmed that ZGlobals is now an OOBTree, but subsequent restarts continue to show the same problem :-( I've placed pdb.set_trace all over the DB state-loading code. When I attempt to step into the state = unpickler.load() line during the loading of the ZGlobals OOBTree, it immediately throws an ImportError on the ZClass GUID. It doesn't even seem to enter the persistent_load or classLoader methods. Tracing this has gotten me all confused. I understand (I think) that when a ZClass instance is unpickled, persistent_load gets the ZClass GUID and uses that to look up the actual _zclass_ class in ZGlobals. What I can't understand is why it would try to import the GUID when loading ZGlobals. All it has it in is strings and the _zclass_ ExtensionClasses, and they should be handled by the normal unpickling machinery, right? 