However, I too would be inclined to go with the crazy, given that he has clearly not implemented a quality content filter - or at least has not done so correctly.
I run a content filter (bogofilter) in several very different environments. One in front of several personal email boxes, which I've never yet had a valid mail get filtered by, and I get high 99% filtering accuracy.
I have a dspam filter in another environment with a few people which has even more accuracy, but is tuned specifically by user, instead of covering multiple users.
My favorite handles around 7k messages per day, and about 20% of the email is users
Content filtering works great - people are just too lazy to do the work it requires to configure it properly, and worse - to maintain it.