I had tried Celena 3.1 when I had my older ATI7000 video card but could never get Twinview to work correctly, so I tried openSuse for a while (because Twinview worked there easily with my old card).
Now I have a new nVidia Dual VGA card (GeForce FX5200) so I just installed Celena 3.1 (got rid of openSuse) and the dual display works like a charm.
I updated to the latest kernel ( -16) and found the same thing.... -16 didn't like the way my xorg.conf was setup at all ....BUT my experience has taught me a few things, such as backing up xorg.conf after a fresh installation
....so when -16 dumped me back at the command line, I copied my original xorg file to xorg.conf, rebooted successfully, used Envy to reinstall my nVidia driver (and by the way, I watched as a new driver was built to work with -16), opened Terminal and ran 'sudo nvidia-settings' to setup my dual display....
....and here I am