I wouldn't call your feelings "immature," Joby - sure, they are a bit petty, but so what? Swooning over Paul is pretty darn petty, too. Lots of thise instinctive sorts of reactions are petty.
I agree with those who say the shiny newness will wear off - the women are just enjoying some attractive new scenery, that's all, and the fact that he's a nice guy as well as good looking is just icing on the cake, if you'll forgive a totally mixed metaphor. They'll get over it.
I also agree with those who say that any attempt on your part to emulate Paul would be ill-advised. You'll feel silly, and you might look silly, too, and you'd also feel phony and just generally yucky. So just go on being the pleasant and valued coworker that you've always been and wait for the whole thing to blow over. Which it will. Trust me. No honeymoon lasts forever.