My host is using SpamAsassin. In the Message Source Header Information gives BAYES_99 BODY: Bayes spam probability is 99 to 100% I like to create a spam filter (in filter settings) based on Message Source (see below) Since filtering on message body is already possible, Seems easy to implement, but How ? X-Spam-Status: No, score=4.3 required=7.0 tests=BAYES_99=1.9,BAYES_999=0.2, FROM_NOT_REPLYTO=0.5,NO_BITLY=1.7,T_RP_MATCHES_RCVD=-0.01 autolearn=no version=3.3.1 X-Spam-Report: * 1.9 BAYES_99 BODY: Bayes spam probability is 99 to 100% * [score: 1.0000] * -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay * domain * 0.5 FROM_NOT_REPLYTO From: does not match Reply-To: * 0.2 BAYES_999 BODY: Bayes spam probability is 99.9 to 100% * [score: 1.0000] * 1.7 NO_BITLY FULL: contains a bit.ly url X-Spam-Level: **** X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mx2.dds.nl