Tiger Server and RADIUS Support?

It appears there is some type of RADIUS authentication support in Tiger server but I cannot really find much detail or if it is really what I can use. I have a Cisco router on which I have a VPN server configured. What I would like is to get away from maintaining the local authentication database and use my LDAP database (to enforce password rules). Is this possible using Tiger's RADIUS support and if so can someone point me to some documentation on how that might be set up. TIA.