Ok, to recap: 1) Add 'import Globals' to the start of the myClass.py file 2) Change the def __init__ in the 'class myClass' definition to: def __init__(self, id, title): myClass.inheritedAttribute('__init__')(self, id) # rest of your __init__ method 3) add the following line at the end of the file (with no indenting): Globals.default__class_init__(myClass) Is this supposed to work and let me instantiate a DataSkin derived class through the 'normal' mgmt interface? if so, something is wrong, because I'm still getting the same error: --8<-------------------------------------- This resource may be trying to reference a nonexistent object or variable _v_dm_ The URL may be incorrect. The parameters passed to this resource may be incorrect. A resource that this resource relies on may be encountering an error. Traceback (innermost last): File /usr/local/Zope-2.2.0-src/lib/python/ZPublisher/Publish.py, line 222, in publish_module File /usr/local/Zope-2.2.0-src/lib/python/ZPublisher/Publish.py, line 187, in publish File /usr/local/Zope-2.2.0-src/lib/python/Zope/__init__.py, line 221, in zpublisher_exception_hook File /usr/local/Zope-2.2.0-src/lib/python/ZPublisher/Publish.py, line 171, in publish File /usr/local/Zope-2.2.0-src/lib/python/ZPublisher/mapply.py, line 160, in mapply (Object: manage_addArchiveImage) File /usr/local/Zope-2.2.0-src/lib/python/ZPublisher/Publish.py, line 112, in call_object (Object: manage_addArchiveImage) File /home/webmaven/Products/ArchiveImage/ArchiveImage.py, line 46, in manage_addArchiveImage (Object: ApplicationDefaultPermissions) File /home/webmaven/Products/ArchiveImage/ArchiveImage.py, line 80, in __init__ (Object: ElementWithAttributes) File /home/webmaven/Products/ZPatterns/DataSkins.py, line 208, in __set_attr__ (Object: ElementWithAttributes) KeyError: (see above) --8<-------------------------------------- For your reference, line 80 in ArchiveImage.py is the first line in the '__init__' function after the 'ArchiveImage.inheritedAttribute('__init__')(self, id)' line, and reads: self.__name__=id I don't know what to try next. Any suggestions? If I zip up the whole Product, could you (or anyone else on the list) take a look at it? I have a feeling I'm missing something obvious. Thanks, Michael Bernstein.