Apple will actively work against any SIM unlocks of the iPhone, says Apple CEO Steve Jobs. Jobs made the comments during a Q&A session that took place after yesterday's press event in London announcing availability details of the iPhone in the UK. When asked by a journalist whether unlocking was a concern for the company, Jobs said, "It's a constant cat and mouse game," according to ComputerWorld's account of the discussion. "We try to stay ahead. People will try to break in, and it's our job to stop them breaking in."

The break-ins that Jobs spoke of have been flying fast and furious in the last month or so. One of the first full SIM unlocks involved using a Turbo SIM card, a somewhat complex process for the average consumer. Then teenager George Holtz published a way to hardware unlock his iPhone with some soldering iron-fu and released instructions for other adventurous unlockers. But none of this was "big" news to the world until the first (commercial) software unlock of the iPhone was announced by iPhoneSIMfree. This sent waves through the iPhone community to push for a free unlock from the iPhone Dev Team, which was achieved just this week with the release of iUnlock, followed by the GUI app to go along with it, anySIM. This app began to appear in the third-party iPhone software update app, Installer, which enabled many iPhone users to install the unlock and experiment with ease.

Hacking is okay... sometimes

Apple's stance on stopping hackers is different depending on the hack. When it came to hacking the Apple TV and introducing the first set of native iPhone applications—something that cannot be done the "legit" way because of Apple's lack of a formal SDK for developers—Apple took a neutral stance. Apple's Greg Joswiak said last week that Apple wouldn't stop anyone from writing the apps or actively work against them, but the company would also not make an effort not to break the hacks when releasing its own software updates. After all, the hacks are not officially supported.

But when it comes to SIM unlocking the iPhone, the game changes drastically. Although Apple has less to lose by customers unlocking the device than AT&T, the company is bound by its contract to AT&T to do what it can to ensure that customers use the designated carrier. And Apple does have something to lose—the company is widely known to be getting a cut of subscription fees from AT&T for each person that buys and uses an iPhone. While it's unclear exactly how much Apple gets per customer, analyst estimates amount to millions of dollars per year in subscription fees going directly to Apple.

Apple's contractual obligations aside, consumers in the US are legally allowed to unlock their mobile handsets after the US Register of Copyrights approved an exemption to the DMCA late last year, noting that "The underlying activity sought to be performed by the owner of the handset is to allow the handset to do what it was manufactured to do—lawfully connect to any carrier." But don't tell that to Apple and AT&T—unless the government bars them from locking out the unlocks, there's virtually nothing stopping them from making sure that the unlocks mysteriously stop working.

A very expensive brick

But we have reason to believe that Apple may go much further than just "breaking" the SIM unlocks that have been released so far. One move that the cat (or is Apple the mouse?) could make in this game would be to permanently and irreparably brick unlocked iPhones when they run this month's pending software update. It would serve as a warning shot to potential unlockers in the future—even if crafty hackers manage to rewrite their unlock apps to get around the changes made in the update, they could always be at risk of suddenly owning a shiny $400 chunk of metal and plastic.

We believe this is a significant possibility, so here's a word for those who have unlocked their iPhones: be extremely careful when the software update lands; let others be the guinea pigs before you run it. A software restore of the iPhone likely won't save you, either, as the radio baseband firmware used to identify the SIM card will still remain unlocked (as it stands now, those who have run unlocks can still do a software restore and have an unlocked iPhone). And if Apple writes its update to make changes to the radio baseband firmware based on what it was expecting, the iPhone will not react well.

Welcome to your new iBrick Extreme: the new paperweight from Apple.