This archive contains the iXhash plugin for the SpamAssassin spam filtering
software, along with an example config file.

Basically the plugin provides a network-based test just as razor2, pyzor
and DCC do. Working solely on the body of an email, it removes parts of it
and computes a hash value from the rest. These values will then be looked up
via DNS using the domains given in the config file(s). You need Net::DNS and
Digest::MD5 installed.

Please note that, while this plugin realises some sort of 'fuzzy checksum',
the fuzzyness is realised by reducing the body text of an email to its
(characteristic) minumum. The MD5 hashing algorithm used is not fuzzy.
Accordingly there are no 'confidence levels' or things of that sort. It's
hit or no hit.

While the plugin has shown to be quite FP-resistant, there may always be FPs,
especially with relatively short emails. USE AT YOUR OWN RISK

For those more deeply interested: This plugin is based on parts of the
procmail-based project 'NiX Spam', developed by Bert Ungerer.([MAILTO]
un@ix.de) If you can read German, read up at [WWW]
http://www.heise.de/ix/nixspam/. The procmail code producing the hashes only
can be found here: [WWW]
ftp://ftp.ix.de/pub/ix/ix_listings/2004/05/checksums 