to enlist Mac addresses

hello: my name is jesus I am making a management settings mac address, I register a user in freeradius-server-02.01.1910 I have a ubuntu 9.10 operating system, and users to modify the plain, unformatted to register a user as follows: jesus cleartest-password: = "jesus" service-type = framed-user framed-protocol = ppp Framed-Compression = Van-Jacobsen-TCP-IP Now as you ago to enlist Mac addresses and what is the syntax or commands? Thanks ...... Jesus R. Cervantes