* lisp/mail/rmail.el (rmail-reply):

Decode subject before matching "Re:" prefix.  (Bug#20396)

1 files changed, 2 insertions, 1 deletions

diff --git a/lisp/mail/rmail.el b/lisp/mail/rmail.el
index 7efcf695b24..43abc128c8a 100644
--- a/lisp/mail/rmail.el
+++ b/lisp/mail/rmail.el
@@ -3830,7 +3830,8 @@ use \\[mail-yank-original] to yank the original message into it."
 ;;;       (setq cc resent-cc)))
     ;; Add `Re: ' to subject if not there already.
     (and (stringp subject)
-         (setq subject
+         (setq subject (rfc2047-decode-string subject)
+               subject
                (concat rmail-reply-prefix
                        (if (let ((case-fold-search t))
                              (string-match rmail-reply-regexp subject))