(mm-charset-synonym-alist): Add :version.

diff --git a/lisp/mm-util.el b/lisp/mm-util.el
index 1ae8480..10dabbc 100644 (file)
--- a/lisp/mm-util.el
+++ b/lisp/mm-util.el
@@ -246,6 +246,7 @@ See `mm-codepage-iso-8859-list' and `mm-codepage-ibm-list'."
                  ,(if (get 'coding-system 'widget-type)
                       'coding-system
                     '(symbol :tag "Coding system")))))
+  :version "21.1"
   :group 'mime)
 
 (defcustom mm-codepage-iso-8859-list