> What kind of spam prevention measures are available for <MTA>?
> What kind of Virus prevention measures are available for <MTA>?
See my list at
http://www.reedmedia.net/misc/mail/filters.html
(some mention specific MTAs and most work one way or another with main
MTAs.)
> How easy is it to setup a virtual domain? and How?
Numerous ways (and there are numerous definitions of "virtual domain").
I do it like the examples found via
http://www.reedmedia.net/software/virtualmail-pop3d/
Also, please consider making a webpage for your user group presentation.
Jeremy C. Reed
http://www.isp-faq.com/ -- find answers to your questions