Using radius client

[Bikrant Neupane]

Hi

I would like the radius client send some optional parameters to my Radius 
server ( running Radiator). How would I do that?
I am authenticating pppoe users  with the radius server. Now I would like add 
some features like MACAddress+UserName+Password authentication. So that I can 
restrict the username on MAC address basis.

I am running PPPoE with radius client on FreeBSD 4.10 and 4.9.

Any help/pointer is highly appreciated.

with regards,
Bikrant