iPhone owners charging Apple and AT&T with breaking antitrust laws asked a federal judge this week to force Apple to hand over the iPhone source code, court documents show.

The lawsuit, which was filed in October 2007, accuses Apple and AT&T of violating antitrust laws, including the Sherman Act, by agreeing to a multi-year deal that locks U.S. iPhone owners into using the mobile carrier.

On Wednesday, the plaintiffs asked U.S. District Court Judge James Ware to compel Apple to produce the source code for the iPhone 1.1.1 software, an update that Apple issued in September 2007. The update crippled iPhones that had been unlocked, or "jailbroken," so that they could be used with mobile providers other than AT&T. The iPhone 1.1.1 "bricked" those first-generation iPhones that had been hacked, rendering them useless and wiping all personal data from the device.

Several days before iPhone 1.1.1 was released, Apple threatened to take action against users who had hacked their handsets, saying that doing so would "violate their iPhone software license agreement and void their warranty." Prior to that, Apple CEO Steve Jobs had said it was his company's job to stymie attempts to jailbreak the iPhone. "It's a cat and mouse game," Jobs said at the time. "People will try to break in, and it's our job to stop them breaking in."

The plaintiffs in the case want to examine some of the iPhone 1.1.1 source code, including that for the kernel, the Core OS and Core Services layer, as well as for two programs -- "Purple Restore" and "BBUpdater -- which are used to update the iPhone's operating system and flash the phone's baseband chip. The source code is necessary, they argued, in order to determine whether all iPhones were given the same 1.1.1 update, and whether it was designed to "brick" all or just some hacked iPhones.

"Unless Plaintiffs are given access to Version 1.1.1 source code, their ability to prove the size and scope of the Class affected by Version 1.1.1 will be severely compromised and unfairly prejudiced," the motion read.

The plaintiffs face a deadline of Jan. 8 for filing a motion to grant the case class-action status. If Ware certifies the class, other iPhone users would be able to join the lawsuit.

According to documents submitted Wednesday to Ware, lawyers for Apple and the plaintiffs met numerous times last summer to hammer out an agreement to give the latter access to the iPhone 1.1.1 source code. As of Aug. 20, 2009, Apple had agreed to make the entire source code of 1.1.1 available for inspection.

But then Apple reneged, the plaintiffs said. "In telephonic meet-and-confer on September 23, Apple began to change its position on how much of the code it would produce, and by October it had changed its position entirely and decided it was only going to produce the baseband firmware portion of Version 1.1.1 and would not produce the portion of the source code that updated the operating system," Wednesday's motion stated.

Apple's excuse, claimed the plaintiffs' lawyers, was that it needed to get the approval of Infineon, the company that makes the iPhone's baseband chip.

"Plaintiffs can wait no longer and request an order compelling Apple to produce the entire code for Version 1.1.1," the motion said.

Lawyers for the plaintiffs have also asked Apple to hand over the engineering documentation for the requested parts of the source code, as well as the manual and software development kit (SDK) for the Infineon chip.