This is to debate issue of a hidden water damage sensor on the i phone 3G. We all know there is one within the headphone jack. My phone has been having technical problems and the Mac. Store declared that there is a hidden water damage sensor, even though there appears to be no water damage in the headphone jack. They claim the hidden one to be in a barely visible location within the charger circuit. We are wondering if anyone else has heard of this issue? Tech support is now saying they have to use a special tool to look at it, but when I was in the Mac. Store, I was not aware of any tools. Thank you.