We use a Barracuda spam firewall to filter spam. However, some spam bypasses the filter by sending directly to the site's IP instead of to the MX record. I'm looking for a way to deny mail sent directly to the server. The catch is I need to be able to do this on a per domain basis, not all domains on the server utilize the Barracuda firewall. I'm guessing this will require custom exim.conf modifications. Anyone know if this functionality is possible via a cPanel-sanctioned method? We'd like the changes to persist across cPanel updates. Sorry if this is posted elsewhere. Hard to search for results when a key term is "MX" and the forums require a minimum search length of 3 characters.