Comment 20 for bug 573101

@David Tombs: This issue is nvidia specific to lucid. Using:
$ apt-cache policy nvidia-96
nvidia-96:
  Installed: 96.43.18-0ubuntu1
  Candidate: 96.43.18-0ubuntu1
  Version table:
 *** 96.43.18-0ubuntu1 0
        100 /var/lib/dpkg/status
     96.43.17-0ubuntu1 0
        500 http://us.archive.ubuntu.com/ubuntu/ lucid/restricted Packages
resolves the issue for me as noted in comment #13. Upgrading to 96.43.19-0ubuntu1 also works.

I have not modified my xorg-server (which is the package is 546578 is filed), I have *only* changed my nvidia-96 driver to resolve the issue:

$ apt-cache policy xorg
xorg:
  Installed: 1:7.5+5ubuntu1
  Candidate: 1:7.5+5ubuntu1
  Version table:
 *** 1:7.5+5ubuntu1 0
        500 http://us.archive.ubuntu.com/ubuntu/ lucid/main Packages
        100 /var/lib/dpkg/status

$ apt-cache policy xserver-xorg-core
xserver-xorg-core:
  Installed: 2:1.7.6-2ubuntu7.4
  Candidate: 2:1.7.6-2ubuntu7.4
  Version table:
 *** 2:1.7.6-2ubuntu7.4 0
        500 http://us.archive.ubuntu.com/ubuntu/ lucid-updates/main Packages
        100 /var/lib/dpkg/status
     2:1.7.6-2ubuntu7 0
        500 http://us.archive.ubuntu.com/ubuntu/ lucid/main Packages

So what specifically is your reasoning for marking this bug as a duplicate of 546578?