Take Two Interactive and Rockstar Games were dealt a blow today as the Entertainment Software Ratings Board, under intense pressure from parental groups and legislators, changed the rating on Grand Theft Auto: San Andreas from M for Mature to AO for Adults Only.

When Grand Theft Auto: San Andreas was released for the PC in June, it was not long before a hacker released a modification to the game that allows players to engage in simulated sex with the main character's girlfriends. Sex had always been in the game, but now it was something that you could actually see, instead of just hearing sexual activity and watching the outside of a house.

There was some dispute as to whether the hacker actually added content to the game or simply unlocked what was already there. The ESRB ruled that the content was included on the disk, and thus justified the higher rating, saying the company failed to disclose it to the board.

Take Two president Paul Eibeler, the publisher of the game, disagreed with the ESRB's position. In a statement released today, Eibeler said the decision to change a game's rating after the fact in response to content added by unauthorized users would create trouble for parents, the industry and anyone who is a consumer of digital content. He said there is no way for anyone to see the extra content without specifically downloading the hack and modifying the game, which would be a violation of the end-user agreement.

The company has halted production of the game, which was the number one selling title across the globe last year. A new version of the game that is supposedly impossible to modify is planned for release in its place. In the meantime Best Buy and Wal-Mart have pulled the game from their shelves.

That move could lead to millions in lost sales, but might take the heat off the industry. Senator Hillary Rodham Clinton has called for increased legislation and stiffer penalties to keep violent or pornographic video games away from kids.

The New York senator also prodded the ESRB to revise its rating for the game. No word yet on whether or not the ESRB will change the rating back once the new unbreakable code version of the game is released.