(message-parameter-alist): New variable.

(message-parameter-alist): New variable.
(message-startup-parameter-alist): New variable.
(message-eval-parameter): New function.
(message-get-reply-buffer): New function.
(message-get-original-reply-buffer): New function.
(message-mode): Make new local variable `message-parameter-alist'.
(message-fetch-reply-field): Use `message-get-reply-buffer'.
(message-yank-original): Ditto.
(message-setup): Get message reply buffer from `message-parameter-alist'.
(message-mime-insert-article): Use `message-get-original-reply-buffer'.