f.status = new EnhancedStatus(550, "5.2.1", longErrorMessage());
f.remoteMtaDiagnosticStatus =
new Rfc821Status(new Response(550,
"Requested action not taken: mailbox unavailable"));
f.remoteMta = new RemoteMta(IP3.getHostName());
f.failureDate = new Date();
f.logId = "NO_1_ENTRY";
return Collections.singletonList((RecipientProblemReport) f);
}