Are you sure it's a facebook icon?
Have you tried a battery pull?
If you go into your Facebook app > Notifications and press U, does it take you to a messages? or Press T, then press the Menu Key and select Mark Prior Open. Does either of those clear it up?
The difference between stupidity and genius is that genius has its limits.
When you take things for granted, the things you are granted, get taken.
Even a mosquito doesn't get a pat on the back until it starts to work.
Too many people miss the silver lining because they're expecting gold.
[BES 5.0.3 / GroupWise 2012 HP2]