How do I update my 3G to ios5.0 (or 5.1) ?? Is it possible?

version: 4.2.1 (8c148)

firmware: 05.13.04

Please help, many thanks

Hi,

Yes, it is possible. You need to use redsnow (grab the latest version from blog.iphone-dev.org) in the Extras section you can find an option 'Custom IPSW' which will create a custom firmware, preserving the baseband. You should then feed the 5.1.1 IPSW to redsnow so it can create a custom IPSW, which you will use to restore your iPhone 3Gs and get to 5.1.1 jailbroken, there you can finally install ultrasn0w and get the unlock.

Let me know how it goes,
Rafael

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