Now that I've finally purchased a spam filtering appliance as a front end to my Exchange 2003 I want to block inbound SMTP from all IPs other than the address that my appliance sends from. I've gone into my Default SMTP Virtual Server, Access, Connection, "Select which computers may access this virtual server" and told it to only accept from the IP of my spam device. The problem is that after doing that I can't access the server from other IPs to relay authenticated outbound mail. Is there a way to allow authenticated outbound SMTP while blocking all inbound SMTP from all IPs other than desired?