Kded4 crashes when using Xinerama. (Kubuntu 13.04 Raring Ringtail)

[Alexander Moldenhauer]

Similer to bug 316514 but involves kded4.

[System Setup]
3 Nvidia GFX cards (GTX 650 Ti Boost, GT 520, 8400 GS), 2 in use, in a multi-monitor multi-gpu setup (i.e. one monitor on one gpu).

[Situation]
Kded4 crashes upon bootup and/or login.
What happens is that anything that uses kded4 will not work. CTRL+ALT+Fn just shows an "_" on screen, ALT+F2 does not work, going into System Settings>Startup and Shutdown>Service Manager reports that KDED4 is not running, and shutdown/restart/logout via application launcher does not work.
Running kded4 in a konsole terminal reports errors regarding "RANDR" not reporting screen data.

["Solution"]
Go to /etc/X11/xorg.conf and comment out/disable Xinerama.

[What should be the ideal solution]
Being able to span a desktop between two or more monitors on different cards without kded4 crashing.