I've used and use RT. It is web based for admin, but all the transactions
are E-Mail based.
http://www.bestpractical.com
I can also make a test queue on my instance if someone wants to play.
--
Larry Rosenman http://www.lerctr.org/~ler
Phone: +1 512-248-2683 E-Mail: ler@lerctr.org
US Mail: 430 Valona Loop, Round Rock, TX 78681-3683 US