Radius user unknown

[Nathan Ridge <ridgey@mackay.matilda.net.au>]

Has anyone seen this problem, have a client running Windows ME using a
standard PPP dialup into our Cisco AS5200 authenticating to radius on a
debian server.  When IP address is being allocated dynamically , it fails
with the following error:

Fri Dec 15 05:06:52 2000: [243] Password =
"\254*SL:\206\033\010S\242\224k~\316\363\323"
Fri Dec 15 05:06:52 2000: [18647] auth: access-request from 203.58.117.4
(203.58.117.4) denied for unknown user bem
Fri Dec 15 05:06:52 2000: [18647] Sending Reject of id 46 to 203.58.117.4
(203.58.117.4)

debugging the cisco reads

Failed because . (3544454646)

BUT if you allocate a static IP in the radius users file, it works
fine??!?!?

any ideas?

Regards
Nathan