Need help authenticating local users on Apple server

Just installed v 2.1.11 on a mac (OSX 6.3) . Freeradius is working with clear text passwords and radtest. According to the wiki, I should be able to authenticate local users accounts without changing anything on the config. That's the way I understood it anyway. However, I am getting "Access-Reject" errors when using local credentials. What documentation specifically addresses authenticating local users? Raymond