Comment 5 for bug 430919

xorg.conf file from Ubuntu v8.10 which shows this all working in an older version.

(Xorg -version)
X.Org X Server 1.5.2
Release Date: 10 October 2008
X Protocol Version 11, Revision 0
Build Operating System: Linux 2.6.24-19-server i686 Ubuntu
Current Operating System: Linux mduncan 2.6.27-14-generic #1 SMP Mon Aug 31 13:01:41 UTC 2009 i686
Build Date: 09 March 2009 10:48:54AM
xorg-server 2:1.5.2-2ubuntu3.1 (<email address hidden>)
 Before reporting problems, check http://wiki.x.org
 to make sure that you have the latest version.
Module Loader present

(lspci)
01:00.0 VGA compatible controller: nVidia Corporation NV44 [Quadro NVS 285] (rev a1)
05:04.0 VGA compatible controller: ATI Technologies Inc Radeon RV100 QY [Radeon 7000/VE]