Originally posted by: DivideBYZero
You don't.
The early Pearls had 5 LEDs under them so they could show multi colors and with the utility ColorPearl you could control color AND whether it was on or off. I would suggest you install that and see if it will control the on/off status. When installed it shows in the Options menu.
The late 8100's, the 8120/30, the 83xx and the 88xx only have white LED's, so no colour fun.
Let me know if it works.
http://www.geekandproud.net/blackberry-software/