Locks up when display is turned off???

[suiteskull]

I have recently run into a problem with my phone locking up when the display turns off or when I turn the display off. I did a quick google search and have found a lot of people having problems with stock phones (mine is a PPCkitchen cooked nuerom). I searched these forums and did not find anything about it. Does anyone have any info on why this is happening? Any fixes other than sending the phone back? With a cooked rom will HTC even warranty it?
TIA