iH8sn0w had released Sn0wBreeze 2.9.5 to support iOS 5.1.1 Build 9B208 for iPhone 4 GSM.Snowbreeze 2.9.5 is for jailbreak iOS 5.1.1 untethered on iPhone 4, iPhone 3GS, iPad 1 and iPod Touch 4G/3G and has no support for iPhone 4S, New iPad/iPad 3 and iPad 2.
Sn0wbreeze is similar to Pwnage Tool as it creates custom IPSW file to jailbreak your device.Pwnage Tool is for Mac OS X whereas Sn0wbreeze is for Windows.
Jailbreak iOS 5.1.1 with Sn0wbreeze 2.9.5 (How To)
Note: It is advisable to back up your files and data using iTunes before proceeding to Jailbreak your device.
1. Download Sn0wBreeze 2.9.5, extract the Zip file and open sn0wbreeze-v2.9.5.exe.
Download iOS 5.1.1 ISPW
2. Click on Next button and then select the iOS 5.1.1 IPSW file which you have downloaded for your device.Sn0wbreeze will now identify the downloaded IPSW file and then click on OK.
3. You will now get four options on your screen iFaith Mode, Simple Mode, Expert Mode and Baseband Preservation Mode.You can select as per your requirement.
4. If you select the Simple Mode then it will create your your custom iOS 5.1.1 IPSW sans customization.
5. Once it has created your custom iOS 5.1.1 IPSW it will ask you to put your device in DFU Mode.Click on OK and follow the on-screen instructions.
To put your device in DFU mode you will have to hold Power and Home buttons for 10 seconds simultaneously and then release Power button but keep holding Home button for more 10-30 more secs.
5. Once your device is in DFU Mode you will be prompted to restore your device using iTunes by selecting the custom firmware that has been created.
Once your device is restored you will have your idevice running on iOS 5.1.1 jailbroken untethered.