I just sold my iPhone 3GS on eBay. I want to restore the phone back to factory and then jailbreak/unlock it. The phone is currently locked to AT&T. It has never been jail-broken or unlocked. The phone firmware is version 3.1.2(7d11) and modem is firmware 05.11.07. I am wondering how I can restore the phone to factory while maintaining the 3.1.2 firmware so that I can use blackra1n to unlock/jailbreak the phone. I have used blackra1n before to jailbreak my iPhone 2G so I am familiar with the process for jailbreak/unlock. I just need help on how to do this since iTunes says it will "restore and update" and I am worried that if I let iTunes do it I will not be able to do what I plan. if I need to jailbreak and unlock it first I can do that. Please just let me know if that is in fact what I need to do. Thank you in advance for some help. Sorry if someone has asked this before.