I accidentally upgraded my iphone 4 to 4.3.5, so jailbroke it using redn0w and then stupidly tried to unlock it using ultrasn0w. The phone doesn't work and cannot be restored in either recovery mode or DFU mode. I took it to a tech guy who couldn't get it to restore either, I'm supposed to go bring back the phone to him tomorrow so he can try something else. Does anyone have any ideas for what can be done? I'm not tech-savvy enough to try myself (obviously) but I want to have some suggestions in case one of them is something he hasn't thought of.