I realize how silly it would seem for a station to not use its own resources to advertise available jock positions, but I think it's a bad idea. Regular listeners, those that do stay with your station through the commercials, have a certain opinion about what radio is like. As a good promotions director would say, we ARE in showbiz. Listeners assume that jocks make the big bucks, and there's just a 'glamour' that goes along with having your voice heard by thousands of people everyday. They tend to put jocks on some kind of 'employment pedestal', thinking "Man, I wish I could do that!" But then hearing a commercial talking about 401k's, insurance benefits, and other 'jobby' things kind of cheapens it in the listener's eyes (ears?).
My $0.02