diff --git a/lib/Qpsmtpd/Auth.pm b/lib/Qpsmtpd/Auth.pm
index 5e3abd1..0b79433 100644
--- a/lib/Qpsmtpd/Auth.pm
+++ b/lib/Qpsmtpd/Auth.pm
@@ -76,7 +76,7 @@ sub SASL {
     else {
         $msg =
             uc($mechanism)
-          . " authentication failed for $user"
+          . " authentication failed for $user from $ENV{TCPREMOTEIP}"
           . ($msg ? " - $msg" : '');
         $session->respond(535, $msg);
         $session->log(LOGDEBUG, $msg);    # already logged by $session->respond