R works on Fedora Core 3

On my system (a Dell 5150 laptop, nVidia GeForce FX Go 5200 with the
nVidia 6629 driver, an internal 15" 1600x1200 panel and an external 20"
Dell 2001FP 1600x1200 panel in non-xinerama dual-display mode), the
X11() device comes up at 7" x 7" on both displays.

Mine works now too.  I think the thing that made it suddenly
start working was that I added 

DisplaySize 336 222

to the Monitor section of xorg.conf.  (This is the screen size in
mm.)  I had a custom xorg.conf, which the installer left alone,
but the xorg.conf.rpmsave did not have this line either.

For more than you want to know about my system see
http://www.sas.upenn.edu/~baron/delli.html

Jon

Jonathan Baron, Professor of Psychology, University of Pennsylvania
Home page: http://www.sas.upenn.edu/~baron
R search page: http://finzi.psych.upenn.edu/