This is making the rounds it seems and it is very frustrating as people panic and rejoice that the Pope is supposedly changing the moral doctrine of the Church. The Pope explicitly said condoms are not a morally sound solution.
He was asked if in any cases condoms could lessen HIV transmission. It's a fact that they can lessen it if other behavior remains constant, even if less than some would believe, but that doesn't make them a morally licit means.
Second, what is a sin in regards to condoms is contraception. Male prostitutes commit the sin of sodomy. Mixing a condom into the mix doesn't change anything since the act was already 100% contraceptive. It's like wearing a condom while you touch--it's no more a sin than masturbating without one on. It doesn't add to the guilt, as far as I can tell and in the case of sodomy it may reduce the possibility of willful murder being added to the sin which already cries out to Heaven for vengeance.
Anyway, even seen in the worst possible light (which I don't see it in), it would be seen like St. Augustine's argument for the toleration of prostitution to avoid greater evils.