One of the bigger complaints about Apple's iPhone -- AT&T's network -- has been solved to a degree by a New Jersey teenager.

The 17-year-old hacker managed to unlock the device so that it can work with T-Mobile's network, the only other wireless operator that uses the same technology as AT&T for its wireless network. It's not possible to hack the iPhone to work with either Sprint or Verizon Wireless.

But don't expect to see a rush of T-Mobile-enabled iPhones anytime soon, even though the N.J. teen posted instructions on his blog. Aside from a complicated bit of coding, the hack also requires the use of a soldering iron and about two-hours of active work.

A previous iPhone hack emerged for European networks, which requires copying user information into Subscriber Identity Module (SIM) cards -- a key element of the GSM wireless system on which the iPhone is built.

Neither method alters the phone functionality much. The iPod music and video features are unaffected completely, and the DRM for all files on the phone remain intact. The only disabled feature discovered so far is the visual voicemail service, which requires direct integration with the wireless operator to function.

Another group calling itself iPhoneSimFree claims to have hacked the device as well, with a method that doesn't require a soldering iron. However the group has not yet released its methods to the public.

There are no laws in the U.S. preventing consumers from breaking the locks carriers place on the phones they sell, unless it's for the purpose of cloning the device. The issue gets murkier if those behind these hacks attempt to sell their method for profit, which could spark a lawsuit from either Apple or AT&T, if not both.

However while the media frenzy over news of the hack has been high, it's not clear consumer demand for such a solution is at the same level. While the idea of a phone that works with any network sounds nice, in the U.S. the only alternate network is T-Mobile. Doing so loses not only the visual voicemail feature, but also AT&T's flat-rate data plan, any software updates and upgrades from Apple, and of course the warranty.

The only real reason to unlock an iPhone is to use it in other countries, where Apple has not yet finalized distribution deals with wireless operators.