diff --git a/DOC/README.test_mailprotocolls b/DOC/README.test_mailprotocolls
index 921e0d2..4ec9022 100644
--- a/DOC/README.test_mailprotocolls
+++ b/DOC/README.test_mailprotocolls
@@ -14,3 +14,10 @@ openssl s_client -crlf -starttls pop3 -connect localhost:110
 openssl s_client -crlf -connect localhost:993
 openssl s_client -crlf -starttls imap -connect localhost:143
 
+
+# Test RSA based TLS connection
+#
+echo "quit" | openssl s_client -connect a.mx.oopen.de:25 -starttls smtp -tls1_2 -cipher ECDHE-RSA-AES256-GCM-SHA384
+
+echo "quit" | openssl s_client -connect a.mx.oopen.de:25 -starttls smtp -tls1_2
+echo "quit" | openssl s_client -connect a.mx.oopen.de:25 -starttls smtp