Ok folks. The latest iOS 5.1.1 firmware can be unlocked with SAM unlock tool provided they have saved their activation tickets.
The people who unlocked via the SAM tool, can create a custom IPSW and run iOS 5.1.1, but right now it's a tethered jailbreak and the untethered jailbreak is also very near!
Create Custom iOS 5.1.1 IPSW to Preserve Baseband For Unlock
Download the latest redsn0w tool.
Download original IPSW for iOS 5.1.1
iOS 5.1.1 Preserving baseband guide:
Step 1: After downloading redsn0w from the link above, start it.
Step 2: Go to Extras > Custom IPSW.
Step 3: Choose the original IPSW file on the iOS device downloaded from the link above.
Step 4: Now the custom IPSW file will be created by redsn0w, the one that has preserved the baseband meaning one will still be on the previous version (baseband).
Step 5: Go to Extras > Pwned DFU to enter Pwned DFU mode. Follow the on-screen instructions.
Step 6: Once there, go to iTunes and press Shift+Restore (Windows) or Option+Restore (Mac).You need to choose the correct IPSW file. It will have a prefix "No_BB".
Step 7: As it's a tethered jailbreak, you need to boot tethered while it's trying to reboot after restoration. To do that, go to Extras > Just Boot!
Now you'll have a custom IPSW on iOS 5.1.1 with a preserved baseband.
Unlock iPhone using SAM 5.1.1 activation ticket backup:
We have heard reports that some SAM 5.1.1 users are stuck again with locked iPhones, but we have tested the guide and we can confirm its works on iOS 5.1.1 tethered jailbreak.
Step 1: Jailbreak your iPhone on iOS 5.1.1.
Step 2: Install SAM on iOS 5.1.1.
Step 3: Revert Lockdown to stock.
Step 4: Replace the backup activation ticket (Lockdown folder) to this path: /var/root/Library/Lockdown.
Step 5: Reboot your device.
Step 6: Disable SAM.
Step 7: Reboot, and then wait for the Carrier Signals to Appears.
Update: Sam Unlock Works on iOS 5.1.1 and iOS 6.0.1
For those who have saved Lockdown folder before using the correct activation ticket you will be able to restore it after iOS 5.1.1 or iOS 6 Jailbreak!
Note: Unlock Activation Ticket is valid 3 years — more info here.
We also posted guide to factory Unlock iPhone 4 using official iPhone unlock.
CONGRATS! You have unlocked your iPhone using SAM backup on 5.1.1 firmware. Enjoy!