(rfc2368-parse-mailto-url): Autoload.

(browse-url-mail): Use it.

lisp/net/browse-url.el

@@ -1301,9 +1301,11 @@ Default to the URL around or before point."
 
 ;; --- mailto ---
 
+(autoload 'rfc2368-parse-mailto-url "rfc2368")
+
 ;;;###autoload
 (defun browse-url-mail (url &optional new-window)
-  "Open a new mail message buffer within Emacs.
+  "Open a new mail message buffer within Emacs for the RFC 2368 URL.
 Default to using the mailto: URL around or before point as the
 recipient's address.  Supplying a non-nil interactive prefix argument
 will cause the mail to be composed in another window rather than the
@@ -1318,14 +1320,24 @@ When called non-interactively, optional second argument NEW-WINDOW is
 used instead of `browse-url-new-window-flag'."
   (interactive (browse-url-interactive-arg "Mailto URL: "))
   (save-excursion
-    (let ((to (if (string-match "^mailto:" url)
-		  (substring url 7)
-		url)))
+    (let* ((alist (rfc2368-parse-mailto-url url))
+	   (to (assoc "To" alist))
+	   (subject (assoc "Subject" alist))
+	   (body (assoc "Body" alist))
+	   (rest (delete to (delete subject (delete body alist))))
+	   (to (cdr to))
+	   (subject (cdr subject))
+	   (body (cdr body))
+	   (mail-citation-hook (unless body mail-citation-hook)))
       (if (browse-url-maybe-new-window new-window)
-	  (compose-mail-other-window to nil nil nil
-				     (list 'insert-buffer (current-buffer)))
-	(compose-mail to nil nil nil nil
-		      (list 'insert-buffer (current-buffer)))))))
+	  (compose-mail-other-window to subject rest nil
+				     (if body
+					 (list 'insert body)
+				       (list 'insert-buffer (current-buffer))))
+	(compose-mail to subject rest nil nil
+		      (if body
+			  (list 'insert body)
+			(list 'insert-buffer (current-buffer))))))))
 
 ;; --- Random browser ---