Is there a way to set the built-in alarm clock so that it will vibrate only (no sound) and still leave the rest of the rings, alerts, etc set to their normal volume? I don't want to turn the system volume down.

Or does anybody know of an alarm/clock program that would do this? Apparently there used to be some on the Palm OS but I haven't found any on WebOS. I'm running a Pre 2 with WebOS 2.1