[Zope] import error - No module named iclass

[Harald Winkelmann]

Uups,
I forgot the subject and the html encoding ....

Hi everybody,

I'm upgrading to zope 2.6.0.
When I try to import a ZClass based Product from zope 2.5.1 i get the
following error. 

Error Type: ImportError
Error Value: No module named iclass

 
Any ideas ???
Harry