-given IP address so that the blocking and relay configuration can be tested. An
-RFC 1413 call is made only if we are running in the test harness and an
-incoming interface and both ports are specified, because there is no TCP/IP
-call to find the ident for. */
+given IP address so that the blocking and relay configuration can be tested.
+Unless a sender_ident was set by -oMt, we discard it (the default is the
+caller's login name). An RFC 1413 call is made only if we are running in the
+test harness and an incoming interface and both ports are specified, because
+there is no TCP/IP call to find the ident for. */