these results are from URL i ve got three sets of spam and ham with about NUMBER messages in each set here s what happens when i enable my latest received header code false positive percentages NUMBER NUMBER NUMBER NUMBER tied NUMBER NUMBER NUMBER NUMBER won NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER won NUMBER NUMBER won NUMBER times tied NUMBER times lost NUMBER times total unique fp went from NUMBER to NUMBER false negative percentages NUMBER NUMBER NUMBER NUMBER won NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER won NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER lost NUMBER NUMBER won NUMBER times tied NUMBER times lost NUMBER times total unique fn went from NUMBER to NUMBER anthony s header counting code does not seem to help neil 