newbie - authentication error

[pkc_mls]

Hi all,

I'd like to tetst my radius conf with a basic setting.
I'm running freeradius-2.0.4-2 on linux debian.

my client.conf contains the following :
client localhost {
                   ipaddr = 127.0.0.1
                   secret = testing123
                   nastype=other
}

I still don't know which kind of parametre I have to set in my 
/etc/freeradius/users file
to allow my radtest to work.

all my tests with cleartext-password, user-password, aht-type, and := =, 
==, leads to the same
error message :
rad_recv: Access-Request packet from host 127.0.0.1 port 57756, id=178, 
length=59
        User-Name = "testuser"
        User-Password = "testpasswd"
        NAS-IP-Address = x.x.x.x
        NAS-Port = 1812
Wed May 28 11:41:06 2008 : Debug: auth: No authenticate method 
(Auth-Type) configuration found for the request: Rejecting the user

next step, how to set up the users file so my local unix users can also 
be authenticated via radius ?

thanks