I got my iPhone on Friday and restored my settings from my old 3g. Today, I got in my car and accidentally pressed the voice control command and slid to cancel it and entered my password. I then set my phone down (I never touched it to my face, so I don't think it was a sensor issue, but I could be wrong) and when I picked it up 5 minutes later, the screen was off and neither the home button or the lock button would respond it it. I tried to hold the power button which didn't do anything either. When I got home I plugged it into my computer and immediately the screen turned on. I had a full battery. Does anyone know what may have caused this or had similar issues?