Comment 10 for bug 62163

Xfce4 is starting dbus in by using dbus-launch in /etc/xdg/xfce4/xinitrc if there is no session bus yet, KDE does not seem to start a session bus.

Xfce4 also seems to start the dbus daemon before the session manager, which may cause similar pain as for the Gnome case if a session-manager-aware program is started through dbus.

Another way is to temporarily special-case the desktop environments in /etc/X11/Xsession.d/75dbus_dbus-launch. This should limit the effect of changes to Gnome.