Version: (using KDE 4.2.85) OS: Linux Installed from: SuSE RPMs I have an option to hide offline contacts on. Sometimes contacts that go offline stay in the list, their status icon is blank. If I toggle the option to hide offlinees twice (show all, then show only those that are online), those contacts are hidden correctly. I'm not at all sure, but it seems that it only happened to Jabber protocol contacts. I don't know, how to reproduce this. I guess, somebody in your contact list should go online and offline several times.
It's Qt bug which is already fixed, fix will be in Qt 4.5.2 (and it's not jabber specific)