Quote of note:

"The editing of any game is a highly technical process," said Take-Two spokesman Rodney Walker. "We liken it to a painter who paints one painting and paints over it on the same canvas."

It is very easy NOT to include previous versions of code on your shipping product. There's a whole class of source code control software, CVS, SCC, SVN, and any shop skilled enough to produce GTA knows perfectly well how to use it.

Take-Two is no stranger to controversy. Previous installments of "Grand Theft Auto" have been adored by hard-core gamers but excoriated by parent groups and lawmakers for their depictions of violence and sex.

In one, players could have sex with a prostitute and then beat her to death and take back their money. That game was rated "Mature" because players did not see the sex. Instead, they saw a parked car rock back and forth.

Why you think I was so harsh and disbelieving? Just do the porn game you want to do.

The ESRB has technical difficulties reviewing the material

The problem is that unlike movies, where raters can see a film in its entirety, video game labels are based on movies of game play that are typically a couple hours in length, plus some random time spent by testers actually trying out the title.

...but if they're serious they don't even need to play the game. They should just view the couple of hours of movies directly.

Anyway...

Hidden Sex Scenes Spark Furor Over Video Game
By Alex Pham, Times Staff Writer

The oversight board that puts parental ratings on video games took the unusual step Wednesday of slapping its strongest warning on a bestselling title as the game maker admitted putting explicit, interactive sex scenes on the disc.

... As late as last week, Take-Two had insisted that the sex scenes were "the work of a determined group of hackers who have gone to significant trouble to alter scenes in the official version of the game." Hackers, the company said, created the scenes by "disassembling and then combining, recompiling and altering the game's code."

... The Entertainment Software Ratings Board began a review to determine whether the scenes were part of the game's original code and warranted a re-rating of "San Andreas," versions of which play on Sony Corp.'s PlayStation 2, Microsoft Corp.'s Xbox and personal computers.

"After a thorough investigation, we have concluded that sexually explicit material exists in a fully rendered, unmodified form on the final discs of all three platform versions of the game," said Patricia Vance, president of the ratings board.

...Take-Two's Walker said Wednesday that the sex scenes were never meant to be seen by the public and that they were revealed only when an outside programmer, called a "modder," wrote software to unlock them.