Group Authorization Question

[Mike Diggins]

I have authentication working from my cisco ASA550 VPN appliance to a 
FreeRadius 2.1.1 server, using NTLM_AUTH for backend authentication. That 
all works. Now I need to add authorization into the mix.

 	1. On the Radius server, I want to add a group X with a list of
 	   authorized usernames.
 	2. On the VPN side, the user selects a profile, and logs in, but I
 	   only want members of group X to be able to connect to that
 	   profile, even if the authentication is correct.

I have no idea how to make the connection between the group profile I 
select on the VPN side, with the group X on the radius side. I'm not even 
sure how (or where) to create such a group with freeRadius. Can anyone 
point me in the right direction?

-Mike