Anti-Spam Agent for Novell NetMail is a replacement for SpamAssassin's spamd. It will tell the NetMail server to send all new email to it for spam checking. If SpamAssassin determines that the email is spam, you can either have it deleted, or have "X-Spam-Flag: YES" added to the message header. This project also includes assistance for others to write their own NetMail agents.
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.
jSieve is a Java implementation of the Sieve mail filtering language defined by RFC 3028. Sieve is an extensible mail filtering language. Its limited expressiveness (no loops or variables and no tests with side effects) allows user created scripts to be run safely on email servers. Sieve is targeted at the final delivery phase (where an incoming email is transferred to a user's mailbox). jSieve is implemented as a language processor that can be plugged into any Internet mail application to add Sieve support.
Apache SpamAssassin is an extensible email filter that is used to identify spam. Once identified, the mail can then be optionally tagged as spam for later filtering. It provides a command line tool to perform filtering, a client-server system to filter large volumes of mail, and Mail::SpamAssassin, a set of Perl modules allowing Apache SpamAssassin to be used in a wide variety of email systems.
AqMail fetches mails from remote mailboxes (POP3), applies admin-defined filters, and stores the email in local mailboxes for POP3 daemons to serve them. It supports virtual mail domains and users. It has been tested with QMail as the MTA and with Spamassassin and ClamAV as filters.
Aquarium is a text filtering package written in PHP. It filters nearly all four-letter words, profanities, curses, and pornographic language from any text, while filtering nearly no benign words. Aquarium can keep your blog, forum, guestbook, or other dynamic Web application clean and suitable for all ages.