gnutls
exim -DSERVER=server -bd -oX PORT_D
****
-client-ssl 127.0.0.1 PORT_D
+client-gnutls 127.0.0.1 PORT_D
??? 220
ehlo foobar
??? 250-myhost
??? 250-SIZE
+??? 250-LIMITS
??? 250-8BITMIME
??? 250-PIPELINING
??? 250-AUTH
auth plain AHVzZXJ4AHNlY3JldA==
??? 503
****
-client-ssl 127.0.0.1 PORT_D
+client-gnutls 127.0.0.1 PORT_D
??? 220
ehlo foobar
??? 250-myhost
??? 250-SIZE
+??? 250-LIMITS
??? 250-8BITMIME
??? 250-PIPELINING
??? 250-AUTH
ehlo foobar
??? 250-myhost
??? 250-SIZE
+??? 250-LIMITS
??? 250-8BITMIME
??? 250-PIPELINING
??? 250-AUTH