This is a Perl/MySQL based content filter designed to work with qmail, Spamassassin and vpopmail. Some aspects of this are still in development (I just don't have the time), but the script has been running on my servers for around 3 months now - and I went from around 4000 pieces a day to around 3 pieces per week. You will have to create your own content match rules - all defined in the zip's README.