post proxy problem

Hi ! I'm trying to set up Freeradius (1.1.0) to proxy ms-chap-v2 and when I get the "accept" from ms-win2k3-ias server, then i want to assign a static ip address. Reading the doc/proxy file, i read that the user file is processed as usual after accept is received ms radius server. users : DEFAULT Service-Type == Framed-User, User-Name == "username" Framed-IP-Address = 192.168.1.100 Running radius in debug mode i alway get this : Error: Warning: Found 2 auth-types on request for user 'username@domain' Is it possible to assign a ip address after a ack (accept) is received from the proxy radius server ? If yes, anybody have a config example for me ?