iXhash.pm is a plugin for SpamAssassin 3.1.0 and up (including 3.2, as far as I can tell). A version compatible with SpamAssassin 3.0 is provided as well.
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.
...
For those more deeply interested: This plugin is based on parts of the procmail-based project 'NiX Spam', developed by Bert Ungerer.(un@ix.de) If you can read German, read up at http://www.heise.de/ix/nixspam/. The procmail code producing the hashes only can be found here: ftp://ftp.ix.de/pub/ix/ix_listings/2004/05/checksums
Instructions
- Go to Please see the unofficial optimized and maintained version at http://ixhash.sf.net and download the current code. Within the archive you find a folder named 'iXhash', there again you find two mailfud.org/iXhash2/ (old official version: https://sourceforge.net/projects/ixhash/)
- Copy 'iXhash2 folders '3.0.x' and '3.1.x'. Unless you still use SpamAssassin 3.0.something go for 3.1.x, which contains the code for current versions of SpamAssassin
2. Copy 'iXhash.pm' and 'iXhashiXhash2.cf' somewhere where SpamAssassin can access it - like /etc/mail/spamassassin. - 3. Edit the first line of ixhashiXhash2.cf (loadplugin) to reflect where ixhashiXhash2.pm is (if not in same directory)
- .
4. Adjust scores. You might want to decrease the scores given in the .cf file first to see if there are too many FPs. You might even want to do some mass checking...if you do, let me know the results
5. if you have to use the ixhash.pm version for SpamAssassin 3.0.x, make sure there' - Run 's no 'ixhash_timeout' line in your *.cf file. This feature is not available with your version
6. run 'spamassassin -D < /some/mail/message 2>&1 | grep -i ixhash', where '/some/mail/message' is a file containing an email. The copious output (on STDERR) This should contain some occurences of 'IXHASH', showing you the plugin is being used. 6. restart - Restart spamd/amavisd/whateverDaemonUsesSpamAssassin