My iPhone 3G with 4.2.1 firmware won't turn on. It goes to the apple boot screen, shows the little apple then after 10 minutes the spiraling white circle comes on like it is trying to respring or go into safemode. i don't know what's wrong, the only thing i did was reinstall notified pro and it resprung into safe mode, so i restarted it as requested and it never fully went to normal or back to safe mode. I've restarted the phone many times, but no luck. Any help would be greatly appreciated.