You can use PwnageTool to upgrade to 4.2.1 (if you have a mac) while retaining your baseband to unlock. Or you can download a custom 3g 4.2.1 ipsw from a website that you can trust.
You can use PwnageTool to upgrade to 4.2.1 (if you have a mac) while retaining your baseband to unlock. Or you can download a custom 3g 4.2.1 ipsw from a website that you can trust.