(Updated 3:30pm Eastern time) Everyone needs a hobby I guess. A New Jersey teenager said today he has hacked the lock that ties Apple's iPhone to AT&T's wireless network, a move that now lets him use it on T- Mobiles network. Experts say T-Mobile is the only other U.S. carrier compatible with the iPhone's cellular technology. But the teenager, George Hotz, 17, isn’t the only one claiming a hacking breakthrough with the iPhone. According to an IDG News Service story posted late this afternoon another site, iPhoneSimFree.com, a company claims it can unlock iPhones through software only. A screen image with an item about the company on Engadget.com also shows an iPhone displaying the T-Mobile name. In addition, John McLaughlin, founder of Uniquephones, said his Belfast, U.K., company will be posting software on Saturday that iPhone users can download to unlock their handsets to work with any Subscriber Identity Module card on any network they choose. The software should hit the Web at Unlock between noon and 2 p.m. Eastern Time, he said. Uniquephones' McLaughlin said 450,000 users already had signed up at iphoneunlocking.com, which the company set up soon after the iPhone was released for people interested in having their iPhones unlocked. The Web site was not active at the time this story was written, but should be reactivated Saturday with options for users to access the unlocking software, he said. The iPhone is based on Global System for Mobile Communication, the most widely used cellular technology, but today the iPhone is sold only in the U.S. and locked into AT&T’s network. Unlocking would allow iPhone owners to break the required two-year contract with AT&T and choose their own GSM carriers. More importantly, it would allow people outside the U.S. to own and use the highly prized device. With an unlocked GSM phone, it's possible to change carriers by putting in a different SIM card. Meanwhile Hotz posted the hack on his blog, said the unlocking procedure is complicated and requires skill with both soldering and software and takes about two hours to perform. Hotz said: “So if you follow these steps, you should have an unlocked iPhone. I'm sorry about how hard they are to follow, but someone will get them to work, and simplify them, and simplify them more. Hopefully a software unlock will be found in the near future.”According to Hotz. the procedure leaves the iPhone's functions intact, such as its ability to access Wi-Fi networks. Hotz said the visual voicemail feature that makes voice messages appear like they were incoming e-mail is the only feature that doesn’t seem to work. It’s not clear US customers would be breaking down the doors for such a development, experts say. It does open up the iPhone for use on overseas carriers networks though. Since the mega-hyped phone debuted in June, computer hackers around the world have trying to break open the device and modify it so it can work with other carriers.According to Hotz’s site he worked online with four other people, two of them in Russia, to unlocking the iPhone.On Engadget, Hotz's work was hailed but tempered. "As excited as I am for this event; that level of soldering and what is at stake is too steep a price. ... This is not the hack for me yet. But, I am super proud of that crew," a reader posted.Hotz also has a YouTube video on the hack. Apple and AT&T have not responded to the story .A complex remote-control work around already exists to get the Skype on an iPhone. TMC Labs uses a complex remote control application, and doesn't actually deliver free calls, though they may be cheaper. And Apple may be preempting this whole thing as it has reportedly signed deals with mobile phone operators to offer its iPhone in three of Europe's largest markets, according to a report in the Financial Times. Germany's T-Mobile Deutschland, France's Orange SA and Britain's O2 (UK) are reported to have signed exclusive deals to sell the iPhone in their respective markets.