I have a class, which contains the logic of a product. class msgList: def __init__(self): self.msgDict = {} self._newId = 0 Then I have another class which takes care of the more Zope related tasks. class mxm_Discuss(SimpleItem.SimpleItem, msgList): def __init__(self, id, title): "Inits the product with default values" self.id = id self.title = title msgList.__init__(self) <-------- Line 22 But when I try to instantiate it in Zope I get an error: "Error Type: TypeError Error Value: unbound method __init__() must be called with instance as first argument" Usually this error comes when I forget 'self' in a method. I cannot see what causes it here though. Has anybody got a clue? It's probably something simple I have overlooked. regards Max M Traceback (innermost last): File C:\zope\zope240\lib\python\ZPublisher\Publish.py, line 223, in publish_module File C:\zope\zope240\lib\python\ZPublisher\Publish.py, line 187, in publish File C:\zope\zope240\lib\python\Zope\__init__.py, line 226, in zpublisher_exception_hook File C:\zope\zope240\lib\python\ZPublisher\Publish.py, line 171, in publish File C:\zope\zope240\lib\python\ZPublisher\mapply.py, line 160, in mapply (Object: manage_addmxm_DiscussAction) File C:\zope\zope240\lib\python\ZPublisher\Publish.py, line 112, in call_object (Object: manage_addmxm_DiscussAction) File C:\zope\zope240\lib\python\Products\mxm_Discuss\mxm_Discuss.py, line 43, in manage_addmxm_DiscussAction File C:\zope\zope240\lib\python\Products\mxm_Discuss\mxm_Discuss.py, line 22, in __init__ (Object: mxm_discuss) TypeError: (see above) - Nørgård Mikkelsen a/s - www.normik.dk - Vandværksvej 18 - DK 5000 Odense C Tlf (+45) 66 14 14 80 - Fax (+45) 66 14 19 43 Max M - Direkte (+45) 63 14 47 15