gdm does not display correctly when run under NVidia twinview

[Ken Pratt]

Binary package hint: gdm

I use a laptop with an external display. The laptop has a built in NVidia card and supports NVIdia's 'TwinView'. When I boot the computer with the external monitor hooked up, the GDM screen shows on the laptop despite the external display being marked as primary and, once I enter my username and password, GDM does not properly process the graphic transition to the gnome session. It draws a background image over a portion of the laptop screen. The image fades to the proper background image. So what I see is a portion of the overall screen Real Estate getting covered up properly by GDM during the login process, but a significant portion not being covered up. This ruins the nice new fade in effect that does work when running with only one monitor. In short, GDM does not seem to recognize the Xinerama settings exposed by the NVidia TwinView mode. (Just my guess)

ProblemType: Bug
Architecture: amd64
Date: Mon Nov 16 14:51:14 2009
DistroRelease: Ubuntu 9.10
NonfreeKernelModules: nvidia
Package: gdm 2.28.1-0ubuntu1
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.31-14.48-generic
SourcePackage: gdm
Uname: Linux 2.6.31-14-generic x86_64