I got the same issue when I updated stuff through Synaptic. I'm not sure what caused it but my guess is a newer version of kdelibs. I have 3.4.2-15. I tried to revert back to the previous version with the force version option, but there are no other 3.4.2 versions anymore. Just the old 3.4.0. My X has already crashed twice, too. It just happened again a few minutes ago. It's never happened to me with Suse 9.3 before lately.
edit: Forgot to say that the change lost all Gnome-based software icons. That's why some are gone and some are not. They're still there but the icon path is missing. I tried to add it back but didn't have any luck with it.
edit again: I found an RPM for the older version, 3.4.2-3. Installed it and all the icons are back. Next time maybe I'll consider twice about updating something that isn't broken. It's just so tempting to have the newest and latest.
Anyway, I assume you have the flawed version that's messing up the icons. In that case, you can get the RPM
here. When you choose a mirror, look at the path to make sure you're getting the RPM for the right Suse version. They're all in the same list.