iOS 4.2 GM was released to developers this week and it seems like it can be jailbroken with the current version of Redsnow (0.9.6 beta2). This should work with all iPhones and iPod Touches but it doesn’t work on the iPad (yet), so iPad users have to wait till Apple releases the official version of iOS 4.2. Also, this doesn’t enable Cydia as it is yet to be released for iOS 4.2. So Cydia and some other custom apps wouldn’t work. You CANNOT unlock your iPhone. Stay away from this if you rely on an unlock. This also requires the new beta version of iTunes 10.1 beta 2 to install 4.2 GM on your iDevice.

These are the iDevices it will work on:

• iPhone 3G
• iPhone 3GS
• iPhone 4
• iPod Touch 2G/3G/4G

To jailbreak, here’s what you need to do:

STEP 1: Download both the iOS 4.1 and iOS 4.2 GM (iOS/firmware links)

STEP 2: Upgrade to iOS 4.2 GM with iTunes 10.1 beta 2.

STEP 3: Launch Redsn0w 0.9.6 beta2 and find your way to iOS 4.1 and click “Open” (NOT iOS 4.2).

STEP 4: Select “Install Cydia” and click “Next“. You can also select the optional choices if you like.

Note: Make sure your device is both OFF and PLUGGED IN to the computer.

STEP 5: Follow the on-screen instructions.

STEP 6: Now sit back and relax while Redsnow does the thing it does best, jailbreak your iDevice. After the process is complete, your iDevice will reboot and you now have a jailbroken iOS 4.2 GM iDevice.