Breaking your child of bad habits.

So my kid talks about his penis constantly. I guess it's to be expected it's kind of a fun part but we just know it's going to start happening at very inoportune moments. Question is: how do we break him of this habbit without giving him a complex? We don't want to start giving him a time out for it because we don't want him to get a complex and start thinking his penis is a dirty bad thing and end up like those f'ed up right wing fundamentalists that refuse to allow sex ed in school then rape little boy's during the church picknic. You know those guys. But it's worse now. It's bad enough that he talks about who has a penis and who doesn't. He once told us that the clock and his mom each had a penis so we corrected him and now he double checks all the time to make sure he understands the concept "the door doesn't have a penis." But we're trying to potty train him now and conventional wisdom (My mom) say's that I'm supposed to let him watch me use the bathroom so that he starts to want to use the potty emulating my behavior. That's cool and all but now he's talking about MY penis and while it's funny when he say's "daddy have a big penis" it's probably going to make people think something COMPLETELY different when he says it at playgroup. You see my delema. Telling him not to talk about it hasn't been working either "I have a penis, but don't talk about it."