lontra@debian:~$ okular
okular(5208) KToolInvocation::klauncher: klauncher not running... launching kdeinit
kdeinit4: preparing to launch /usr/lib/kde4/libexec/klauncher
klauncher(5212) kdemain: No DBUS session-bus found. Check if you have started the DBUS server.
kdeinit4: Communication error with launcher. Exiting!