In Fedora 13:
In Applications --> Electronics --> Circuit and PCB design --> KiCad:
If you open Eeschema and then attempt to add a new component to the
component libraries as an ordinary user, you can't. That is because
everything in /usr/share/kicad/library is owned by root. That's a bug, I
think you would want to move the libraries out of /usr to some other
location that can be made writable to by a user. The intent of the
software is to allow users to add components to the component libraries.
I think Wordpress in Fedora 11 and 12 had this same problem of
directories which should be user-writable located under /usr for a
while, and then it was fixed.