A seguir a minha dica para os usuários que obteve o erro a seguir ao executar o VirtualBox no openSUSE 13.1:

“Qt CRITICAL: startkdeinitlock(20745): couldn’t create slave: “Cannot talk to klauncher: Not connected to D-Bus server”
klauncher(20956) kdemain: No DBUS session-bus found. Check if you have started the DBUS server.
kdeinit4: Communication error with launcher. Exiting!
Qt CRITICAL: startkdeinitlock(20745): Couldn’t start knotify from knotify4.desktop:  “KLauncher could not be reached via D-Bus. Error when calling start_service_by_desktop_path:
Not connected to D-Bus server”

Solução, execute o comando precedito do parâmetro KDE_FORK_SLAVES :

KDE_FORK_SLAVES=1 virtualbox 

virtual-box