3gs Factory Unlock story. THANKS MASSIE!
I bought an AT&T 3GS locally from someone who upgraded. I JB it and was going to unlock it for T-Mobile, but all the instructions were making me dizzy...... I found out that AT&T might unlock it... thanks to the suggestion of Massie here on the forum. After trying to call AT&T several times I finally got someone to create an Unlock case# for me. They asked me to fax a bill of sale with my contact information and someone would contact me within a week. Not wanting to wait a week I called the previous owner who agreed to call AT&T (instead of giving me all their account info) and request the "Unlock". Later that day the previous owner forwarded the email from AT&T stating to do a back up and restore in iTunes. So, after three failures and trying a different computer and ending up with the "Plug into iTunes I realized that the JB/Cydia was probably causing the problem. I fixed it with Tiny Umbrella, and then un-installed Cydia and then did a complete remove and restore. The R&R was still going 8 hours later so I did a hard reset, plugged it into iTunes and "Walla"! A while later is says: Congrats your iPhone is Unlocked! It works great on T-Mobile now.
Thanks again Massie