clapf is an email content filter application. It includes a statistical (inverse chi-square) anti-spam module, interfaces to several anti-virus products, a minefield (blackhole), spam quarantine, support for various RBL lists, training utilities, and much more. It can be used as an after queue content filter with Postfix (including as an appliance) or via a local delivery agent (LDA), preferably maildrop.
License: zlib/libpng License
Changes:
This release adds experimental language detection. It adds a kind of backscatter detection using a special email header. Extended whitelist support. Primitive token reassembly logic to get 'Cialis' from 'C i a l i s'. You can forward messages to be trained to ham@ and spam@ in daemon mode. The username/UID vs. email address query has been redesigned. You can store these assignments in either a MySQL database or in an LDAP database/Active Directory. A new Web UI replaces the CGI applications. The LDAP admin part is not ready yet, but it's fairly usable and much nicer.
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