The Anti-Spam SMTP Proxy (ASSP) Server project aims to create an open source platform independent SMTP Proxy server which implements whitelists, Bayesian, and virus filtering to help stop unsolicited commercial email (UCE). Anti-spam tools should be adaptive to new spam and customized for each site’s email patterns. This easy to use tool works with any mail transport and achieves these goals requiring no operator intervention after the initial setup phase.
MailStripper Pro is a mail scanner that aims to remove spam and viruses from incoming mail. It recognises and decodes many obfuscation techniques used by spammers and uses several different mechanisms to recognise spam which are immune to Bayes poisoning, and has achieved real-world success of over 99.8%. It is MTA-independent and does not implant itself into your mail server. Instead, it functions as a proxy, allowing the MTA to reside on a different server.