Less than two weeks after the first tools for performing an untethered jailbreak on iPhone, iPad, and iPod touch models running iOS 5.1.1 were released, the iPhone Dev Team has released updated versions of its jailbreak utilities.
The latest versions of redsn0w will jailbreak most iOS devices.
Ultrasn0w 1.2.7 can carrier unlock an iPhone 3GS or iPhone 4 running iOS 5.1.1 — assuming you still have a supported baseband. And PwnageTool lets you update an iPhone that’s already been carrier unlocked to iOS 5.1.1 without updating your baseband — thus preserving the ability to use the phone with a wireless carrier that may not officially be supported.
You can find download links for redsn0w 0.9.12b1 for Windows or OS X and PwnageTool 5.1.1 for OS X at the iPhone Dev Team blog. Once you’ve jailbroken your device you can install ultrasn0w 1.27 from the Cydia Store.