+ #############################################################################
+ # This check is commented out because it is recognized that not every
+ # sysadmin will want to do it. If you enable it, the check performs
+ # Client SMTP Authorization (csa) checks on the sending host. These checks
+ # do DNS lookups for SRV records. The CSA proposal is currently (May 2005)
+ # an Internet draft. You can, of course, add additional conditions to this
+ # ACL statement to restrict the CSA checks to certain hosts only.
+ #
+ # require verify = csa
+ #############################################################################
+