In Ubuntu 12.10 Alpha "Quantal Quetzal", man gdm works. I'd also suggest you read /usr/share/doc/gdm/README.Debian which explains a bit about /etc/gdm/greeter.gsettings where you can configure several parts of GDM.
I'm going to go ahead and close this bug since it seems fixed. ** Changed in: gdm (Ubuntu) Status: Triaged => Fix Released -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/514866 Title: no man pages for gdm To manage notifications about this bug go to: https://bugs.launchpad.net/gdm/+bug/514866/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs