[Zope] eGroups clone with zope?

[kellan]

The Online Policy Group (affiliated with the EFF) is looking to build a
free, open alternative to YahooGroups, essentially web-based interface to
managing and participating in mailing lists, potentially with a file
manager, and polls as well.

When we talked about the project, I was sure I would find software that
already fit our requirement spec.  In particular I expected that mature
frameworks like ACS or Zope would be sure to have a product that provided
this.  So far though I've drawn a blank.

However Zope is still pretty new to me, so I might be missing some obvious
solutions that already exist.

Has anyone built an eGroups clone for Zope?  Or integrated existing
products to
provide similiar functionality?

-or-

Can someone reccomend the best course to go about building such a beast?

Obviously Zope already can handle user management - creation,
authentication, etc...  And I've seen products for polls, and bulletin
board systems.

But is there some existing tools that either provide a standard
majordomo/mailman style mailing list, or integrate with one?

Advice would be greatly appreciated.

Thanks
kellan