[Zope] Adding mixin class does not work with Python 2.2/Zope 2.5.1

[Kevin Smith]

I have a class that overrides the __bobo_traverse__ method to put parts 
of the URL into request variables.  I'm not sure when it broke, but it 
isn't working in my Python 2.2/Zope 2.5.1 setup.  A simple example that 
breaks is as follows:

from OFS.Folder import Folder
class TraversableObject: pass
class TraversableFolder(TraversableObject, Folder): pass

I get an error message about an empty or missing docstring even when 
putting an empty class in front of Folder in the superclass list.  Does 
anyone know how to fix this?

Kevin Smith
Kevin.Smith@sas.com