From the description:
MissingLight is a tiny app that turns on the BlackBerry's status LED if you miss a call. A BlackBerry uses the status LED for many notifications: incoming call, voice mail, SMS, email etc. Unfortunately, the ability to indicate a missed call is curiously missing from my particular model (BlackBerry Curve 8320 from T-Mobile). MissingLight is my attempt to fill in this missing functionality for the status LED, hence its name.
To use, just install the app. This application might request access to your phone log when you first install it: don't worry, it only uses your phone log to detect missed calls. If you miss a call, MissingLight will make your status LED blink purple. Because there is only one such LED, different signals can conflict. The missed call light can temporarily turn off the coverage indicator if you enabled it (blinking green). The missed call light can in turn be overridden by the voice mail indicator (blinking red).
I am making this program temporarily available for download for a few days. It's free for you to use. I only ask that you let me know if it works on your particular BlackBerry model.
OTA Download:
http://the-wongs.net/chris/bb/MissingLight.jad