Automate Add Auth Usrs to Pwr Users Grp

We recently migrated to a new W2K domain (Native Mode). I need to add Authenticated Users to the local Power Users group on all my PCs. All PCs are running W2K. I tried using the cusrmgr tool included in the Resource Kit but it doesn’t recognize the Power Users group. I did run it from a domain admin account. (It did work when I added a domain group to the local Admin group.)

Does anyone know how I can automate this task? I really don’t want to have to Manage each PC and manually add users if I don’t have to!

Thanks in advance!