* lisp/gnus/mml1991.el: Make it loadable.

* lisp/gnus/mml2015.el: Comment.

Fixes: debbugs:13456

lisp/gnus/ChangeLog

 2013-05-09  Glenn Morris  <rgm@gnu.org>
+	* mml1991.el: Make it loadable.  (Bug#13456)
+
 	* gnus-art.el (gnus-article-date-headers, gnus-blocked-images):
 	* gnus-async.el (gnus-async-post-fetch-function):
 	* gnus-gravatar.el (gnus-gravatar-size, gnus-gravatar-properties):

lisp/gnus/mml1991.el

@@ -50,6 +50,8 @@
 (autoload 'message-options-get "message")
 (autoload 'message-options-set "message")
 
+(require 'mml2015)
+
 (defvar mml1991-use mml2015-use
   "The package used for PGP.")
 

lisp/gnus/mml2015.el

@@ -47,6 +47,9 @@
                   (config &optional minimum-version))
 (declare-function epg-configuration "ext:epg-config" ())
 
+;; Maybe this should be in eg mml-sec.el (and have a different name).
+;; Then mml1991 would not need to require mml2015, and mml1991-use
+;; could be removed.
 (defvar mml2015-use (or
 		     (condition-case nil
 			 (progn