spamassassin - perl e-mail filter to identify spam

Spamassassin is an intelligent email filter which uses a diverse range
of tests to identify unsolicited bulk email, more commonly known as Spam. 
These tests are applied to email headers and content to classify email using 
advanced statistical methods.  It has a modular architecture that allows 
other technologies to be quickly wielded against spam and is designed for 
easy integration into virtually any email system.

spamassassin requires:
- for basic functions, perl-digest-sha1, perl-net-dns and perl-html-parser. 
- for sa-compile (to compile regex into c code): re2c.
- for sa-update (to update spamassassin rules): libwww-perl.
All required packages are available from SlackBuilds.org.

For advanced functions it may rely on other (optional) perl modules.