"Pope Benedict XVI says in a new book that the use of condoms can be justified in some cases, such as for male prostitutes seeking to prevent the spread of HIV. "
riddle me this: why is the Pope making declarations about what is justifiably permissible within sinful behavior?! it's like the NFL saying, "while engaged in an ejectable offense, the player is justified in keeping his helmet on for his own protection" (no pun intended)..
..or better yet, "while robbing a bank, it is justifiable to wear a bullet proof vest."
Because people are weird like that. Even while committing adultery, some people still won't use condoms if they are think that using them is wrong. I know that's blatantly inconsistent, but consistency is something that the human race hasn't been particularly good at.