domain security problem

hi, my configuration: radius 2.X , win 2003 AD, domain: TEST, 802.1x I have a problem: If the pc is in the domain(TEST) it can authenticate good. If it is not in domain it can't auth, it is good, BUT when i set the computer name to TEST and it is not in the domain(simple workgroup) it CAN authenticate. I use ntml_auth for the authentigation. ntlm_auth = "/usr/bin/ntlm_auth --request-nt-key --domain=%{mschap:NT-Domain} --username=%{mschap:User-Name} --challenge=%{mschap:Challenge:-00} --nt-response=%{mschap:NT-Response:-00}" How can I fix this risk? What are the solutions?