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There are some external projects that maintain their own rule sets, but these are not part of the Apache SpamAssassin project so while rules posted there will possibly be used by some advanced users, the entire user community will not have access to them. Note that they are unable to contribute rules to Apache since the original author must make the contribution.
- the http://www.exit0.us Wiki
- the SARE forums at http://www.rulesemporium.com/forums/
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