The University of Illinois at Urbana-Champaign uses this email system: Mirapoint
http://www.mirapoint.com
http://www.mirapoint.com/company/news_events/press/20020820.shtml
George Mason University uses this email provider: iPlanet
http://wwws.sun.com/software/
James Madison University uses this email system: iMap
http://www.imap.org/
Virginia Community College System (VCCS) uses these email providers:
Pine System: http://www.washington.edu/pine/faq/whatis.html#top
Elm System: http://www.instinct.org/elm/doc/Elm-FAQ.txt
Zeus: http://www.zeus.com/