There is a way to do it is just a little hard to do. Basically if you could find a way of doing an ARP request to the computer, then you could find out the mac, but that would require you being able to access the computers hardware to make the request. Its easy with a router to find the mac by doing an arp request, but you should be able to do the same from a pc, just a little harder. Plus each time someone logs on it would have to do a queury to find out their mac. I would love this feature because I have people that sign up after being banned because they are smart enough to know that if they change nic's or get a program like smac or even in some nic's you can change the mac like say in routers... then you can get a new ip and get back on.
There are ways of doing this... hopefully someone comes up with the feature because I would sure love to implament it...
