iPhone 4 Unlock might take long. New Baseband OS will require rewrite of ultrasn0w

That’s right. Unless you got a factory unlocked iPhone 4, which is available almost everywhere except the US right now, you wouldn’t be able to carrier unlock your iPhone 4 for some time to come. While iOS 4 on iPhone 3G and iPhone 3GS has already been unlocked with ultrasn0w 0.93, the baseband OS in iPhone 4 is completely different.pmb9800

iPhone 3G and 3GS have a different baseband CPU than the iPhone 4 hence running different OS as well.

The iPhone 3G and 3G[S] both ran Nucleus OS on thePMB8878 baseband CPU (aka XGold 608), where the iPhone 2G ran the PMB8876 (aka S-Gold 2). iPhone 4 uses the PMB9800, or X-Gold 618 – running a separate OS – ThreadX, an RTOS by ExpressLogic.

Before the unlock, the iPhone 4 needs to be jailbroken as well. Once that’s been done, the work on an unlock will start. Don’t keep your hopes up on getting a locked iPhone 4 and using it with another carrier anytime soon. A safe bet would be to get a factory unlocked version.

Of course, we’ll keep you updated on any progress on this. Stay tuned! [via ModMyi]

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  1. Damn, I want to buy an Iphone 4 ASAP, I just had my Unlocked I-phone 3G stolen at Busch Gardens two days ago, and am now forced to use a sidekick since I have T-mobile.

  2. This sucks. I'm itching to get the new phone but I really need the carrier unlock. Not to escape AT&T here, but to use it overseas when I travel a couple of times a year. As if I'm going to pay AT&T or anybody's international roaming! Isn't locking something we own unconstitutional? Is this grounds for a class action lawsuit?

  3. If you're in the US, just take a quick trip up to Canada in a few months and buy an unlocked iPhone in an Apple Store.

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