In the Admin Guide for Juniper UAC 3.1, there's a Use Case on page 156: Using an External LDAP Server for MAC Address Authentication. Have you tried following those instructions? We are currently using an LDAP server for MAC Address Authentication. It's a Sun LDAP server but the configuration should be similar for AD 2008. You just need to store the MAC address somewhere in the AD tree. We use the objectClass ieee802Device to store hosts with their MAC address. Best regards, Steven ... View more