Restricting individuals from sending mail to groups in the directory?

I am using Lotus Notes Domino 5.0.8, and I have created a user group including all users. I use this group for sending e-mail to all accounts, but I want to give access rights to this group. For example, I want person X to send mail to everyone, but person Y cannot do the same. How can I do this?
You cannot restrict individuals from sending mail to groups in the Domino Directory. The group lookups are a function of the server. So, even if you were to hide the group document with a readers field, as long as the user knows the group name, they can still send mail to that group.

This was first published in October 2002