Update 2 : We just confirmed with @Musclenerd one of the Dev Team Members that this is a hoax, this will not unlock the iPhones, any of them, for more then 10 seconds at least 
Best advise from MuscleNerd the lower you stay on your iOS version the better your chances are of getting a compatible jailbreak, when it will be finally released.
Update 1 : We have verified that this method does not work, soon as the TMSI is refreshed the phone will restart and ask to activate again, hence the video is cut of so quick at the end.
We’ll keep you updated once the real unlock hits the web.
Seems like there is news flying around everywhere that is stating that you can unlock your iPhone 4S on firmware iOS 5.0 and iOS 5.0. We have not confirmed this but will in a few hours when the other microsim arrives, please post comments below so we can find out if this is fact or fiction.
Here are the steps based on the video:
- Insert original carrier AT&T SIM card.
- Dial 611 for AT&T customer service hotline and drop the call.
- Turn on Airplane Mode.
- Take out AT&T SIM card.
- Insert T-Mobile SIM card.
- Make sure WiFi is off (he also tapped on ‘Forget this Network” to make sure it doesn’t connect automatically later).
- Switch off Airplane Mode and iPhone will search for network. This is followed by the Apple splash screen appearing.
- Activation Required will be displayed on the screen.
- EDGE network will activate automatically – notice the ‘E’ on the top left corner of the screen.
- Wait for about 20-30 seconds and turn off the phone.
- Turn on iPhone and the same Activation Required screen will be displayed.
- When you see one signal bar, tap on Use Cellular Connection.
- Eject SIM card. Wait about 7 seconds, then pull out T-Mobile SIM.
- Activation Required screen will be displayed the second time. Now slide to unlock go to home screen and now put in AT&T SIM card.
- Insert SIM card. It will show the Apple logo and say “Activation Required” for the second time.
- Unlocked! Do the same thing as before, tap on Use Cellular Connection.
- This time wait 7 seconds, then quickly pull out the AT&T SIM card and put in the T-Mobile SIM card.
- Unlocked!
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