Upgrading Unlocked Iphone 3g Firmware Help

[nox88]

I already have a Iphone 3g that was soft unlocked and jailbroken using redsnow which is on 3.0 FW.

How would I go about upgrading to 3.1.2 because I hear there is a problem with the baseband when upgrading and you need a custom FW so the baseband does not change.

A guide would be great

[Krunk83]

Yeah, you can't unlock now with 3.1.2 but on Nov. 3rd Geohot is releasing a unlock(blacksn0w) to go with the jailbreak(blackra1n). After this 3.1.2 with baseband 05.11.07 will be unlockable.