Just a little while ago, @iH8Sn0w released an updated version of Sn0wbreeze 2.4 beta 1.
This version of Sn0wbreeze 2.4b1 jailbreak iPhone 4, iPhone 3GS, iPodTouch 4G, iPodTouch 3G & iPad 1G running iOS 4.3.1. iPhone 4 & iPhone 3GS users can follow these instructions to Jailbreak & Unlock your device on iOS 4.3.1. iPad & iPodTouch users can follow the below step by step guide to jailbreak your iDevice. Keep in mind that this is a tethered Jailbreak.
Step 1: Download the required Files – Links posted at the bottom of the post
Step 2: Launch Sn0wbreeze 2.4 BETA 1 and Click Ok on the disclaimer.
Step 3: Click Next – Blue Arrow in the bottom right corner
Step 4: Click on Browse, Navigate to the Original iOS 4.3.1 firmware and Click Open
Step 5: Let it verify the IPSW file. Once Verified Click Next
Step 6: Now, click on Expert Mode (Selecting Baseband Prservation Mode will only preserve your iPhone baseband. It will not Jailbreak your iPhone)
Step 7: Now, Click on General and then click on Next
Step 8: Check mark Install SSH and then Click Next (optional)
Step 9: Now, If you want to add any custom packages add them here. If not, just click Next
Step 10: Now, Click on Build IPSW and Click Next to cook custom firmware.
Note: By now, Snowbreeze should create custom cooked IPSW file for your device. And you will also notice a iBooty Folder for iOS 4.3.1. You need this to tethered boot into your iOS device.
Step 11: Once the custom firmware is cooked, Connect your iOS device and turn it OFF.
Step 12: Now, follow the on screen instructions to put your iOS device in PWNED DFU mode.
Step 13: Once your iOS device in PWNED DFU mode, Launch iTunes
Step 14: Hold down SHIFT KEY and Click on Restore on iTunes, Navigate to the custom cooked IPSW file, which should be saved on your desktop, and click on Open.
Step 15: Now, just sit and relax, iTunes will take care of the rest.