I recently encountered the 'No module named iclass" problem when upgrading from Zope 2.5 to 2.6l, and discovered a nice, simple solution: 1) Export the troubled product as an XML file. (This worked for me in Zope 2.6 though Zope 2.6 woudn't otherwise touch it. You can, of course, downgrade, then export if it doesn't work under 2.6 for you.) 2) Load the XML export file into your favorite editor (I used xemacs), and search for the string "iclass". It will be found in a section that starts something like: <object> <klass> <global id="10712.92" name="Interface" module="Interface.iclass"/> </klass> 3) Delete the enclosting <object>...</object> section. 4) In the ZMI remove the troubled project, then import it from the modified file. For me, this process worked perfectly. -Greg