Generate In-Reply-To header according to draft-ietf-drums-msg-fmt-05.

diff --git a/lisp/message.el b/lisp/message.el
index bc367d3..34b5773 100644 (file)
--- a/lisp/message.el
+++ b/lisp/message.el
@@ -2943,17 +2943,21 @@ to find out how to use this."
   "Return the In-Reply-To header for this message."
   (when message-reply-headers
     (let ((from (mail-header-from message-reply-headers))
-         (date (mail-header-date message-reply-headers)))
-      (when from
-       (let ((stop-pos
-              (string-match "  *at \\|  *@ \\| *(\\| *<" from)))
-         (concat (if (and stop-pos
-                          (not (zerop stop-pos)))
-                     (substring from 0 stop-pos) from)
-                 "'s message of \""
-                 (if (or (not date) (string= date ""))
-                     "(unknown date)" date)
-                 "\""))))))
+         (date (mail-header-date message-reply-headers))
+         (msg-id (mail-header-message-id message-reply-headers)))
+      (when msg-id
+       (concat msg-id
+               (when from
+                 (let ((stop-pos
+                        (string-match "  *at \\|  *@ \\| *(\\| *<" from)))
+                   (concat " ("
+                           (if (and stop-pos
+                                    (not (zerop stop-pos)))
+                               (substring from 0 stop-pos) from)
+                           "'s message of \""
+                           (if (or (not date) (string= date ""))
+                               "(unknown date)" date)
+                           "\")"))))))))
 
 (defun message-make-distribution ()
   "Make a Distribution header."