I've read myself silly trying to understand this, so I'm really hoping someone can help clear this up for me. I'm looking for an iPhone to use on T-Mobile, so unlocked. I was told by someone to look for an iPhone that is 3.1.2 or earlier firmware. Then, I've been told by someone else I need to look at the modem firmware and make sure it is not 05.12.01. So if someone has a 3GS that is 3.1.2 but 05.12.01 does that mean it cannot be unlocked? How would a phone get the updated modem firmware 05.12.01 but still be on 3.1.2? Thanks for your help.
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clarification for a newbie please
- Thread starter jdlindsey7
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If you have a 3GS with 5.12.01 and 3.1.2, that means your phone was upgraded to 3.1.3 and then downgraded using a cached signature hash. Such a phone can be jailbroken but, sadly, is no longer unlockable.