I got my iphone 4 in the morning. Few hours later I noticed there is a tiny scratch on the back. It seems to be caused by something very sharp. All I can recall is that I just put it in my pocket for 20 minutes with my keys but none of those keys are sharp enough to make scratch like that. I'm 90% sure that this scratch comes from factory producing. I didn't check it carefully when opening up the box because I never thought this things could happen. Is there anyone who also found a scratch and believes it comes from factory?