On Tue, 10 Feb 2009, Ben Klein wrote: [...]
Application tried to create a window, but no driver could be loaded. Make sure that your X server is running and that $DISPLAY is set correctly.
Interesting. xauth problem. Again, I'd be surprised if this happened with sudo. Not so surprised if it happened with "su -".
X access will very often be broken after a sudo or an su (e.g. Debian). In fact I believe it will only work on distributions which install special PAM packages. For all others you should use gksu, kdesu or sux.