adding content file extension handles

[Guest_imported]

I've been getting hit by code red requests a lot lately on my personal server and its making it a real pain for me to look through my logs, and i stumbled across this page on slashdot

http://www.dasbistro.com/default.ida

I need some help setting it up since i normally don't mess that deep with my apache server (I am quite willing to learn). Making the users aware that code red is jumping off their machine is a good public service announcement i think.
Anyway the problem goes "how do i associate files with the ".ida" extension as perl CGI scripts?

Thanks for the time.