If all you want is an unlock, downgrading to 3.1.2 won't help as it will not downgrade the baseband. There is no unlock available for 3.1.3.
For a 3G (assuming your sig is correct) you can just download a 3.1.2 FW and shift-restore but there really isn't much reason to.
Don't mean to hijack, but one is still able to jailbreak 3.1.3, correct?
OP, like others said, there's really no reason to downgrade; assuming I'm correct (and pending correction), you can still jailbreak at 3.1.3 and, besides, there's no unlock hack for 3.1.3 or 3.1.2.
Don't mean to hijack, but one is still able to jailbreak 3.1.3, correct?
OP, like others said, there's really no reason to downgrade; assuming I'm correct (and pending correction), you can still jailbreak at 3.1.3 and, besides, there's no unlock hack for 3.1.3 or 3.1.2.
Don't mean to hijack, but one is still able to jailbreak 3.1.3, correct?
OP, like others said, there's really no reason to downgrade; assuming I'm correct (and pending correction), you can still jailbreak at 3.1.3 and, besides, there's no unlock hack for 3.1.3 or 3.1.2.