[any ANONYMOUS forum user]

I recently had to restore my jailbreak/unlocked iPhone 3G and it forced me to upgrade to 3.1.3. So obviously I no longer am able to unlock my phone for T Mobile network. Is there a way to get rid of the new version and downgrade my itunes back to 3.1.2? Any help/links/advice would be greatly appreciated.

[Stream Recorder]

You can Jailbreak iPhone 3.1.3. And you can unlock it. Google has lots of links for that.

And you can downgrade iTunes as well if you need.