Permissions with gdm and consolekit

[Christoph Pleger <Christoph Pleger cs tu-dortmund de>]

Hello,

I have been using pam_devperm.so for a long time. pam_devperm.so is a
PAM module that, with my configuration, changes the ownerships and
permissions of some device nodes in /dev when a user logs in on :0, so
that the device nodes belong to that user and get permissions 600.

Now I realized that if gdm is used as display manager and additionally
consolekit is installed, the permissions are set to 600, but then they
are reset to 660.

What does gdm do that causes the permissions to be changed if
consolekit is installed?

Regards
  Christoph