The first thing you have to do is go here: www.felixbruns.de and download Apple’s original 3.1.3 firmware .ipsw file to your desktop. Then go here: ih8sn0w.com and download Sn0wbreeze v. 1.5 to your desktop and unzip it. Then run Sn0wbreeze as shown on my video and follow the instructions. After Sn0wbreeze creates your custom 3.1.3 firmware on your desktop you need to go here: ih8sn0w.com and download iREB to your desktop and unzip it. Run iREB as shown on my video and follow the instructions. Then open up iTunes, then press and hold down the shift key and click on Restore now select the custom firmware that was created by Sn0wbreeze on your desktop and click ok now iTunes will start restoring your iphone once done your iphone will be jailbroken on firmware 3.1.3.!! PLEASE DO NOT USE FIRMWARE 3.1.3 !!! IF YOU ARE GOING TO WANT YOUR IPHONE UNLOCKED. WITH 3.1.3 YOU WILL BE LOCKED TO AT&T If you want your iphone unlockable USE FIRMWARE 3.1.2 IN PLACE OF 3.1.3 and follow all the same steps.