I am trying to re-jailbreak my iPhone 3G with the 4.2.1 OS. I turn the phone off, press the "power" button and home button (after turning the phone on), and it just boots up normally. It will not let me get it into DFU mode. I tried doing this for about 4 or 5 hours last night, and ANY help will be greatly appreciated. Thank you.
-CJ
-CJ