blue rectangle covering 'system tray' icons

[Brian Norman Wootton]

I've mentioned this before, I have this blue rectangle which covers or 
partially covers
system tray icons, at the moment it's covering the volume icon, but at 
different times it covers 'eth0', hplip, skype, time and date. It's also 
now corrupting the date/time and
covering the dolphin icon, it's annoying rather than earth shattering 
and it seems worst
when I'm emailing kubuntu-users-request. Has anybody got anything 
similar, has anybody got any answers? I'm using T-Bird on kubuntu 8.10 
on 64b amd.
brian