I've been trying out the ubuntu 8.10 beta and I think I've run into a problem. I don't want to post it as a bug until i'm sure that its not just my mistake.

Under the System-Administrations-Authorizations, I set the Implicit Permission of Active Console from Yes to Admin Authentication. But this had no effect. I was still able to Shutdown. However, the permission Shutdown the system while others logged in does work.

Have I forgotten to configure something properly?