I got an Otterbox (IMPACT) case for my wife's Droid Eris. I have verified that when the case is on, the proximity sensor does not operate at all. Take case off, works fine. Case is on correctly (there's not a whole lot of ways to have it on wrong). Pressing it harder onto my head (which one shouldn't have to do) or holding it farther away don't help, either. Anyone else have this? Does the other Otterbox case do this? Anyone want to buy a gently used Otterbox? Cheap?