Hello, I'm having a strange problem with Zope and I'm hoping someone has seen a similar problem and can give a direction to look next. At this point, I'm totally baffled at the problem. I have a muli-thread application. I recently added a python class and derived it from SimpleItem to make the class persistent in the Zope DB. As soon as I did this, Zope started to fail on me, giving me the traceback shown in the attachment. Let's call the class 'info'. It is instantiated in a class 'person' and all instances of class person exist in the folder called 'personcontainer'. I checked the initialization and the folder gets properly populated with all 'person' objects. If the class in is defined: class Info: ... all runs well, but my instances are not persistent. If the class is defined: class Info(SimpleItem): ... then when the program iterates on the objects in the personcontainer, using personcontainer.objectItems() no person instances are found. Thanks for any help, suggestions and thoughts. Jim Anderson