Hello! I've got a bit of a complicated problem here. It came in my mind to go 4.0 and above on my 3.1.3 iPhone to have that neat battery percentage, multitasking and compatibility with most iPhone apps. I put my iPhone in recovery and tried to apply 4.0 on it, without even informing myself, thinking i was able to do such an "easy task", hence I jailbroken before. Unfortunately it failed, and I didn't even know how to get out of the recovery(RecBoot...) so, the biggest damn mistake one can do, I installed 4.2.1... Now here is the problem, I downgraded it to 3.1.3 again, jailbroken, but my baseband is 05.15, and I want to know if there is anything I can do to revert it. I heard rumors here and there that if I update to iPad baseband, I can revert it back to a lower one, and on the other side some said it's a terrible mistake applying iPad baseband(GPS, along with some others) I have also been told I can do it with a custom ipsw. I do not have SHSH blobs or anything saved, wich can prolly be a problem. Any ideas what possibilities may be? Thanks in advance.