acSMTP is a SMTP/POP3/IMAP mail server for Win32. May serve MX hosts and in-LAN mail. Black/white lists for IPs/Emails, RBL spam blocks, DNS Email validation, optional DBMS backend for lists and rules, custom user authorization, AntiVirus API.
http://www.ziddu.com/download/7008531/acSMTP-update-3996.rar.html