I am using OpenSUSE 11.3 with KDE 4.4. I changed hostname of the machine and noticed that the menus of KDE goes blank. The icons are still there and I can still see the description when I hover over the icons.
Removing /home/.kde4 (or better yet backup the folder) and a reboot fixed it. Is it the right way of doing it? I don't know but I am back to business. Of course my customization where all gone.