[Zope] export of modified ZClass fails

[Dennis Allison]

Dieter Mauer responded:
>
>Dennis Allison writes:
> > I modified ZDiscussions significantly and it works fine. It's a ZClass
> > with Python base classes.   I want to export it to another Zope instance.
> > So I simply exported it from the Control_Panel/Products menu in the ZMI.
> > Export worked fine but when I import it in the new system, I get a 
> > diagnostic 
> > 
> >   Failed to import class _ZClass_for_ZDTopic from module Products.ZDBase
> > 
> > Products.ZDBase defines the ZDisscussions base classes.  It was installed
> > successfully in a separate, independent import.
>Did you restart Zope after you have installed the ZDBase product
>(and before you imported the zexp)?
>
yes, I did.  In setting up the new site I wrote a configuration program that moves
in and installs all the various products repeatably so I have a stable base.  The 
ZClass portion ot the ZDiscussions (the zexp file) even gets copied into import for 
ease of installation.  Just to be sure, I repeated the export process and everything
worked.  Such Heissenbugs bother me.  I'm guessing that I may have mistyped one of 
the names or something.  Anyhow, for the moment all is well.

Thanks/