Proxy DHCP-requests

[newuse at qip.ru]

Hi all, I am newbie in setting up FR 2.2.3, I am trying to proxy all request coming from dhcp to an other RADIUS server, but I can't setup FR to do this.
I was trying the fowling:

 cat ./raddb/sites-enabled/dhcp
server dhcp {

listen {
        ipaddr = 255.255.255.255
        port = 67
        type = dhcp
        interface = eth0
        broadcast = yes
}

dhcp DHCP-Discover {
        update reply {
               DHCP-Message-Type = DHCP-Offer
        }

        update reply {
                DHCP-Domain-Name-Server = 8.8.8.8
                DHCP-IP-Address-Lease-Time = 7200
                DHCP-DHCP-Server-Identifier = 172.16.1.1
        }

        update control {
                Proxy-To-Realm := DEFAULT
        }
#       ok
}

dhcp DHCP-Request {
        update reply {
               DHCP-Message-Type = DHCP-Ack
        }

        update reply {
                DHCP-Domain-Name-Server = 8.8.8.8
                DHCP-IP-Address-Lease-Time = 7200
                DHCP-DHCP-Server-Identifier = 172.16.1.1
        }

        update control {
                Proxy-To-Realm := DEFAULT
        }

#       ok
}

#  If there's no named section for the packet type, then the packet
#  is processed through this section.
dhcp {
        # send a DHCP NAK.
        reject
}


}

The proxy.conf here:
cat ./raddb/proxy.conf
proxy server {
        default_fallback = no
}

realm NULL {
        authhost        = 172.16.1.5:1600
        accthost        = 172.16.1.5:1601
        secret          = testpass
}
realm DEFAULT {
        authhost        = 172.16.1.5:1600
        accthost        = 172.16.1.5:1601
        secret          = testpass
}


Please, help to find mistake.