Header data does make sense?!

I am investigating why all mails from a certain mailing list I have joined 
are classified as spam by razor-check. Everything I have read states that 
headers do not affect classification, but if I replace the headers the 
same message actually passes! Have I misunderstood something about how the 
filter works?

-- 
Regards,
Tobias

-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys - and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV