>line 23, in IWorkspace value_type=Object(title=u"Object", > description=u"adsf"), in zope/schema/_field.py class Object(Field): __doc__ = IObject.__doc__ implements(IObject) def __init__(self, schema, **kw): <---- you need to pass a schema as a non key-word if not IInterface.providedBy(schema): raise WrongType Sincerely, Mats Nordgren