How to get the server to respond with Access-Challenge ?

Hi, I would like to know how to make the RADIUS server (freeRADIUS 1.0.0-pre3) to send a challenge to the NAS. That is, instead of getting Access-Accept or Access-Reject, I want to see Access-Challenge. What do I need to set in the user's profile ? I tried looking thru the FAQ and some archives but could not find anything. RFC 2865 states that "if the server decides to send a challenge ..." - I want to know what makes the server to send the challenge. I am using the plain ascii/pap/chap/mschap kind of authentications. Any help appreciated. Thanks, Sarav __________________________________ Yahoo! Mail - PC Magazine Editors' Choice 2005 http://mail.yahoo.com