[mabmarc]

I just had the same crack as you. Just below the dpad above the USB port. The back cover of mine also cracked right at the upper left corner from removing it and switching batteries.

I took it to sprint and told them the phone was dropping calls (which it was, twice on 2 calls with strong signal) and showed them the cracks. So the tech took 45 minutes to look at it and came back and said the signal was strong and that the cracks were cosmetic and didn't affect the phone. I told him the Dpad was sticking and causing the numbers to rotate by themselves on the call screen. He said he would just order a new one and to come get it next tuesday.

So I did, I have a new touch diamond now. I never dropped the old one either. I also never got it wet but the wet strip was all red. I don't think the dpad ever worked right on my old phone. The new phone seems much more responsive.