Filtering email messages for canned ham

Evidently, Nanog@merit.edu doesn't accept emails with the four letter word interpretation of my subject line. I have a machine which is the primary MX for my network, a linux box running Qmail (1.03) which scans every inbound mail to my domain for viruses before being passed on to the secondary MX, an Exchange Server. That works well, so I'd like to break the whole thing by adding to it some means of filtering out UCE / <Canned Ham> ;) Anyone used or know of tools that are written for Qmail's interaction ? Thanks, Rick Smith Director of Technical Services Applied Tactical Systems (A division of Vertex Interactive, Inc.) <http://www.atsworld.com> --- <http://www.vertexinteractive.com> (973) 808 - 1750 x382