[Zope] ERROR ZODB.Connection Couldn't load state for 0x04

[Mark Gibson]

Zope 2.9.7

Apparently, I've done something bad and created "cross database 
reference".  At least, that's what I gather from googling the ZODB error.

I have 3 filesystem storages.  One contains a ZCatalog that references 
objects in the other.  Is this the cause of the error?  I can't start 
zope now - how can I recover from this?

2009-04-13 10:46:24 ERROR ZODB.Connection Couldn't load state for 0x04
Traceback (most recent call last):
   File "/home/zope/zope_2_9_7/lib/python/ZODB/Connection.py", line 732, 
in setstate
     self._setstate(obj)
   File "/home/zope/zope_2_9_7/lib/python/ZODB/Connection.py", line 786, 
in _setstate
     self._reader.setGhostState(obj, p)
   File "/home/zope/zope_2_9_7/lib/python/ZODB/serialize.py", line 617, 
in setGhostState
     obj.__setstate__(state)
AttributeError: keys