Changing focus with arrow keys

[Vebjorn Ljosa]

I just switched to xfce4 from gnome + sawfish, and I love it!  There
is one thing I miss, however: Sawfish (with the addition of some code
I found on the web) allowed me to change focus to the window east,
west, north, or south of the current one.  I had the functions bound
to Super + the arrow keys, and it was very convenient.

Is there a way to get the same functionality with xfce4?

Thanks,
Vebjorn