Anti-Spam SMTP Proxy Server 1.2.1

The Anti-Spam SMTP Proxy (ASSP) Server project aims to create an open source platform-independent SMTP Proxy server which implements whitelists, Bayesian, and basic anti-virus filtering to rid the planet of the blight of unsolicited email (UCE).

What features make ASSP great?

Easy browser-based setup (optional).
Uses your existing message transport and existing SMTP server.
Works with Sendmail, qmail, Postfix, Imail, Exchange, Courier, Mercury, Lotus Notes, and all other standard SMTP servers.
Runs on Linux, Unix, Windows, OS X, OS/2, and more.
Automatically customizes to your site’s unique email profile.
Automatic whitelist — noone you email will ever be blocked.
Senders receive immediate notification if mail is blocked but no erroneous bounces are ever generated.
Basic anti-virus filtering using the ClamAV virus databases.
Redlist keeps an address off the whitelist.
No-processing addresses pass through.
Makes use of honeypot type spambucket addresses to automatically recognize spam and update your spam database.
Bayesian filter intelligently classifies email into spam and non-spam.
Supports additional site-defined regular expressions to identify spam or non-spam email.
Can optionally block all non-whitelisted email (for anti-spam zelots).
Mime encoded and other camouflaged spam is also recognized.
Automatically maintains the spam and non-spam databases.
Accepts whitelist submissions and spam error reports by authorized email.
Optionally rejects executable attachments from non-whitelisted (or all) addresses.
Free (as in speech) software — Licensed under the GPL.
Practically no maintenance required.
Active user community and email list for support questions.
Source code included if you need to customize your installation.
Runs as a service in Windows NT / 2000.
Optionally blocks no mail but adds an email header and/or updates the message subject.
Optionally uses community-based spam statistics to identify hosts that are likely to send spam or non-spam mail.
In *nix environments can switch to non-root user. Also supports chroot jail.
Individual users can be configured to receive all mail.
Shows detailed analysis of spam rating process for specific messages.
Option to forward a copy of every rejected mail to an address.
No perl modules to install — runs complete “out of the box”.
Can block spam-bombs (when spammers forge your domain in the from field).
Keeps spam statistics for your site.
Detailed up-to-date documentation.
Can listen on more than one smtp port.
And much more!

Download: Anti-Spam SMTP Proxy Server 1.2.1 Windows, Linux, BSD, IBM, OS/2