At&t Adieu : Hackers Release iPhone 4 Unlock

[zamemba99]

ultrasn0w now works for the iPhone 4, allowing owners to take their iPhones off AT&T.
Fewer days after opening the iPhone to non-Apple software with the simplest jailbreak procedure yet, hackers have further liberated Apple’s iPhone 4 with a carrier unlock, which frees owners from AT&T by allowing them to use their iPhones on any GSM network.
After jailbreaking an iPhone 4 with the simple, Web-based unlock released earlier this week,

owners can download an updated version of ultrasn0w that now works on the iPhone 4, iPhone 3G and iPhone 3GS. It’s available for free today through Cydia, an app which acts as a distributor of software (similar to Apple’s own App Store) on jailbroken devices.
As with previous iPhones, a jailbroken and unlocked iPhone 4 will be able to make voice calls and access the EDGE data network on T-Mobile, but does not support the frequencies required for 3G speeds. (AT&T uses 1900MHz for 3G, while T-Mobile uses 1700MHz and 2100MHz, frequencies the iPhone 4 does not support.)
Check out the video tutorial below from @TechTechManTV for step-by-step directions.

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