Binding MAC to IP Statically

[Colin Watson]

Any way to bind a MAC address statically to an IP?. I wish to do this to prevent a user from changing his IP address on the subnet, so if he does he can't pass traffic. I have experimented with ipfw, but I can't quite see how I could accomplish the binding of a IP statically to a nic's MAC. Any ideas be appericated.

Many Thanks

Colin