Ah, so it's not actually aged inside an animal, but it is made with animal products. Huh. Good to know. Of course, that seems to apply more strictly to Parmigiano-Reggiano, which must be made according to traditional methods, but I'm sure you can find a parmesan-style cheese that's vegetarian if you're careful about checking your labels.
"And we are all told from the moment we open our eyes, that everyone is entitled to his or her opinion. Well, thatís horsepuckey, of course. We are not entitled to our opinions; we are entitled to our informed opinions. Without research, without background, without understanding, itís nothing. Itís just bibble-babble. Itís like a fart in a wind tunnel, folks." --Harlan Ellison