When I use some KDE tools, most recently Konqueror, I get symptoms of a mis-configuration which I think is dbus-related.
I've never fooled with it as far as I can remember, and I know nothing about it.* So I'm hoping there's an easy cure.
The recent thing: opening a Konqeror windows for a freshly-mounted CDROM on a freshly-rebooted system: a dialog box
"A security policy in place prevents this sender from sending this message to this recipient, see message bus configuration file (rejected message had interface "org.freedesktop.Hal.Device.Volume" member "Mount" error name "(unset)" destination "org.freedesktop.Hal")