I have a problem with Ubuntu precise.

I expect the "envelope" from the messaging menu to turn blue only where there is a pending notification (like a new mail or a new IM message). When I click it, I usually see from wich app the notification come from.

Sometime, the envelope turn blue, but there is no notification. When I click the envelope, I don't see any app with notifications pending. I can "clean" the notifications to change the color to white, but the envelope will turn blue again after some minutes.

The only solution I found is to reboot the computer...

Is it a known bug? I didn't find anything about that after a Google search.

Thank you.