(smtpmail-via-smtp): Only negotiate starttls on

streams that were opened using starttls.

diff --git a/lisp/mail/smtpmail.el b/lisp/mail/smtpmail.el
index 78393348c5dfd86379a5585f52fbd7f474197426..82fbfdad5ed3ce96a701bddd77d4bfaede97cd63 100644 (file)
--- a/lisp/mail/smtpmail.el
+++ b/lisp/mail/smtpmail.el
@@ -613,7 +613,7 @@ This is relative to `smtpmail-queue-dir'.")
            (if (and do-starttls
                     (smtpmail-find-credentials smtpmail-starttls-credentials host port)
                     (member 'starttls supported-extensions)
-                    (process-id process))
+                    (numberp (process-id process)))
                (progn
                  (smtpmail-send-command process (format "STARTTLS"))
                  (if (or (null (car (setq response-code (smtpmail-read-response process))))