pulling dn for User-Profile from ldap

Hi. I'd like to give users an option to specify which network to connect to using something like helpdesk\username@realm admins\username@realm I was thinking of stripping the network part in hints and saving it in a variable say Preferred-Network and then match on it in users DEFAULT Ldap-Group="%{Preferred-Network}" User-Profile := "%{Profile-DN}" Profile-DN would be matched to seeAlso in ldap.attr and seeAlso would be an attribute containing dn of the radius profile to be used for this group. However when I set it up I didn't see ldap module returning Profile-DN and I couldn't match against it. I guess I'm using the ldap module wrong but I'm not able to figure it out. thanks for any pointers martin