Apple may have finally solved the problems preventing white iPhone 4s from being mass-produced, a source claims. As has been suggested before, one of the main dilemmas is argued to have been getting the right paint thickness -- specifically on the front panel, though, and in a way that doesn't affect the proximity sensor or create light bleeds. A complicating factor is said to be the need to silkscreen the paint on in a way that leaves a gap for the LCD.