CyanogenMod 7 for Milestone A853 RC15 Android rom has been updated again, with a bug fix and some logs and some application code clean up, also some Italian and Russian translation update.
The issue is that when we make a call to somebody or receive a call from someone without any headphone, and enable the “volume rocker wake up” option, we can not using the volume buttons to change the call volume, except we put the phone away from ears, in other words, when we speak to someone we can’t change the call volume until turn on the screen, that is because the proximity sensor disables screen wake using power button. With the “volume rocker wake” option enabled in CMParts, volume keys emulate the power button whenever the screen is off. If the screen is off due to proximity sensor, volume keys will become useless. This description came from the github.