Ok. First hold the power and home button. Once the screen goes black, release the power button but keep holding the home button and connect your iPod cord to your iPhone. It should be in restore mode. Now download this firmware:
http://appldnld.apple.com.edgesuite....2_Restore.ipsw and save it somewhere safe and you can easily locate.
Once that's done, open iTunes and hold in shift + click restore if your on a PC and hold in option + click restore if your on a Mac. Locate where you save the firmware we downloaded before. Wait for the process to complete and jailbreak your phone using ZiPhone:
ZiPhone Download Server - IPhone and IPod Touch Software
Good Luck.
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