Since verizon requires authentication for their smtp http://forums.verizon.com/t5/FiOS-Internet/SMTP-relay/td-p/1....
For postfix or zimbra which also uses postfix, it's done by
Zimbra has products for several Linux variants but you could run a similar underlying structure using postfix, dovecot or cyrus, and something like squirrelmail as a web interface.
"Endless money forms the sinews of war." - Cicero, www.freedomshift.blogspot.com
Want DP delivered to your inbox daily? Subscribe here: