http://www.macnn.com/articles/10/06/17/hack.for.iphone.4.may.be.forthcoming/
ultrasn0w unlocks iOS 4 on older iPhone 3GS models
updated 11:05 am EDT, Thu June 17, 2010
Hack for iPhone 4 may be forthcoming
A new version of ultrasn0w has been released, allowing some iPhone 3GS owners with the iOS 4 gold master to unlock the device for use with unofficial carriers. The main limitation is that users must have the v04.26.08 baseband, retained through earlier hacks. ultrasn0w will thus not be (immediately) useful for newer 3GS models.
ultrasn0w 0.92.1 will also not apply to the final iOS 4 firmware, due on June 21st, and by extension the iPhone 4, which ships on June 24th. Another update of the software will be required, and this is due only sometime after next week's product launches. "Please be patient," ultrasn0w's developer remarks.
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Joined: Nov 2005
05.11.07
Use Blacksn0w for 05.11.07.