I have an 3g iphone and I'm looking to jailbreak it. It has 4.2.1 on it and firmware is 05.15.04. I've tried usin greenpois0n gp_win_rc6.1, but I guess I'm doing something wrong. Just read that greenpois0n won't work on a 3g. Now I know why it didn't work. So what's the best way to jailbreak a 3g iphone?