i jailbroke my phone but it started to get too slow so i updated it with itunes and put the original software back on. Iwas planning on re-jailbreaking it but when i follow the exact same steps all i get is a big fat error 21 can anyone help me or is 2.2 software jailbreak a one time only thing? i have also heard of downgrading my firmware is a good way to do it too, any suggestions?