Thanks for all those who tried the MacFilterCallout dll. As you all must have checked out by now that Link Layer Filtering feature is a part of Windows Server 2008 R2 DHCP Server. DHCP Server team has come up with a GUI based tool which will let an administrator import the MAC addresses specified in MACList.txt file (used by MacFilterCallout dll), into the allow/deny list of Windows Server 2008 R2 DHCP Server.
This tool will work only on Windows Server 2008 R2 or above. DHCP Server role must be installed and the service must be up and running. Comments corresponding to each MAC address entry can be edited in place before you import the entries into the DHCP Server database.
DHCP Server Team