Integrating Spam Assassin with your Mail Transfer Agent.
I would first take a look at IntegratedInMta (Sendmail, Postfix, Qmail)
Here are links to documents on how to integrate SA with Mail Transfer Agent
Exim -
Content Scanning with Spamassassin Documentation Page.
CommuniGate Pro (CGP) - Try CGPSA, available at
http://www.tffenterprises.com/cgpsa/
CommuniGate Pro (CGP) - CGPAV can do SA and ClamAV, available at
http://program.farit.ru/
Postfix First Step - Basic Integrating - at
http://onetforum.com/fourm/viewtopic.php?p=27
Postfix Secound Step - Basic Integrating with SPAM Quarantine - at
http://onetforum.com/fourm/viewtopic.php?p=63#63
NoSpamToday! SMTP Proxy Seamless SpamAssassin Integration Into Any Existing E-Mail Environment - No Spam Today! requires just a few mouse-clicks to integrate SpamAssassin into any existing Email infrastructure (supports Windows™ NT/2000/XP/2003 and Linux) - at
http://www.nospamtoday.com/server/
eWall - is a programmable SMTP proxy for any mail server, allowing to create flexible filtering scenarios, using set of pre-defined conditions/actions and JavaScript engine. Among other features, eWall supports antivirus software (ClamAV, AVG, Avast!, CA eTrust, etc. ) and of course, can be integrated with SpamAssassin. There's a special video guide on
this page.
Training
Guru Labs course GL275 - Feaures in-depth Spamassassin coverage (lecture and lab exercises) including MTA integration with Sendmail using milter and Postfix integration both after and before queueing
