It should work as long as you are using an HTC PhoneCanvas (unless mike left out some dependencies, which would mean you could just flash a better ROM). You can find Psensorstatus and change it to 1 in the registry (see below). The proximity sensor will then be on all of the time though and it resets to 0 every soft reset. When you build the ROM right or use a stock ROM, it changes to 1 during a phone call and shuts off when you hang up.
HKLM\System\State\Phone
PSensorStatus=1
I also wrote a mortscript to enable it for non-htc phonecanvas's, but the mortscript runs all the time. I'm not sure what effects it would have on battery life or if it would just be less of a drain to leave the psensor on all of the time. I stopped using it when I couldn't find a way to get it to only activate during a phone call and shut off when the call ended. I'm sure it could be done if one knew how to write a program, but I don't think mortscript can do it. If you use the mortscript, you need to make sure you have mortscript installed first.
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