Comment 41 for bug 1304805

A better fix is to run:
sudo apt-get install qdbus

This will remove an existing 32-bit package and replace it with 64-bit. After running this, it worked fine for me without needing to change the quotes in startkde.

I saw this here: https://liquidat.wordpress.com/2013/04/29/short-tip-fix-qdbus-problems-during-a-kubuntu-upgrade-to-13-04/