Just an FYI....

Novell Netmail was bought out by Messaging Architects a short while
ago.  If you're unfamiliar with it, Netmail was the scaled down version
of GroupWise email, engineered to handle large number of accounts and
large volumes of email with as little overhead as possible. It runs on
Windows, Linux, and Novell servers, and supports multiple client
protocols (IMAP, POP, etc) and includes a web interface that provides
both email and calendaring.   Anyway, since taking over development of
the product from Novell, they have begun offering it free to educational
institutions for student email accounts:

http://www.messagingarchitects.com/en/industries/Education/FreeEmailForStudents.asp


This is not a hosted solution, where your accounts are on their
servers. This is the software for free, to run on whatever hardware you
prefer in your own environment.  You can download it for free to play
around with, or seen an online demo from the links at the bottom of the
page.  Share and Enjoy.