shutdown or reboot from gdm

[Paul Galbraith]

I'm running woody and have gnome installed, and everything seems to be working fairly well, except that there's no shutdown or reboot option available from the desktop.  From the docs I've seen, it seems like gdm should offer this option after I've logged out from gnome, but it doesn't appear to.  The gdm docs mention a system menu where reboot/shutdown should be an option...I assume this is after I've logged in?  There no system menu in the login window that gdm presents.  Does anyone know what I need to do to be able to shutdown/reboot from the desktop (aside from su shutdown in a term window)?