Question on DNS Routing...

ok. I have my little network running Windows Server 2003 - I have over 500 users, but there are 2 students who are plugging into my network using windows XP systems. The names are generic, so I can't detect which one of the 1000 students it is, but I want them off my network, It was recommended to me to route them to a bogus DNS address using their mac address, but I'm not sure where to start (I do have their mac addresses off my server) . . . Help

From a command line type "nbtstat -a ipaddress" without quotes.

Code:

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H:\>nbtstat -a 10.10.100.3
Local Area Connection:
Node IpAddress: [10.10.100.3] Scope Id: []
          NetBIOS Remote Machine Name Table
      Name              Type        Status
    ---------------------------------------------
    ComputerName        <00>  UNIQUE      Registered
    DomainName          <00>  GROUP      Registered
    ComputerName        <20>  UNIQUE      Registered
    DomainName          <1E>  GROUP      Registered
 
    MAC Address = 00-26-B9-CE-8C-26

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