Yes there is a known problem Gerald, as Jim says, it happens when there is a new PM (Personal Message) addressed to you - Read the message and the problem will vanish, at least until the next PM is sent!
I think I have a solution for it, but I don't want to start playing around with the code at this time of the night, especially after a few cans of the amber nectar.... I'll try my mods in the next day or so when I'm sober!!

Eddy