How to Unlock a version 3.1.2 iPhone 3G or 3Gs
Unlock and jailbreak your iPhone! You can either reinstall the entire operating system, wiping all the data from your phone, or you can wait for Black Snow to come out. In the method shown in the video, you can unlock right away. To restore, hold option (on a Mac) or shift (on a PC) and click restore. After it is done restoring, you should be getting an error message that the phone isn't registered and to insert a SIM card. Insert the SIM card you want to use. Close iTunes and open up www.blackra1n.com. Download the program. Load the program and restart the phone. Find some Wi-Fi. Open and download Cydia, Rock, and sn0w for use with your phone. Install your applications, then delete Blacksn0w. Enjoy your unlocked and jail-broken phone!