As this kinternet tray icon works on plasma, there may be something wrong with razor tray panel plugin.
Images show plasma panel and razor panel below.
Most of my KDE4 panel icons do not display in Razor-qt - I think that is either a design choice (Razor-qt does not use Plasma) or a result of the short time it has been in development.
Well, it can display nvdock icon just fine.
Kinternet, kshutdown and kmplayer all have this black cover, so I thought it’s qt3 specific.
Going to run a different panel for a while, probably xfce or kicker.
It displays hplip perfectly; I assume KDE uses a different approach to system tray icons from external providers.