I am currently evaluating a Raq4 box. I am looking to implement some mail filtering rules. ie, for SPAM

Does anyone have any information on implementing mail filters on a RaQ? or if you could point me to any good resources.

Thanks,
Dave

Have a look at this threads:

http://www.webhostingtalk.com/showthread.php?s=&threadid=32898

http://www.webhostingtalk.com/showthread.php?s=&threadid=36737

For general informations you can check:
http://spam.abuse.net/adminhelp/mail.shtml