Pretty sure this is upstream and not distro specific.
It is exactly the same as 'solved' bug number 394 but under latest git build.
http://bugs.trinitydesktop.org/show_bug.cgi?id=394
Running tdesu (from guest console or superuser menu item) kills klauncher and nothing from tmenu or tray will launch, instead receiving the error message: "Klauncher could not be reached via dcop"
Running tdeinit fixes the error.
To reproduce open a guest console and run 'tdesu kwrite' then close and launch something from tray.
My build is from latest git. Can someone confirm this behaviour? Regression?
Kind Regards,
Jay