Writing and Testing New Rules
See the custom rule writing help wiki and German Ruleset: http://www.exit0.us/
We assign scores when we do a major release using the GeneticAlgorithm. Some details on how we do that are in RescoringProcess.
If you write custom rules, you really need to test them using a hand-classified set of mail messages divided into spam and non-spam collections – see HandClassifiedCorpora – and the mass-check tool – see MassCheck.