Have smtpmail.el prefer the From: header for the MAIL FROM envelope

* mail/smtpmail.el (smtpmail-send-it): Prefer the From: header
over `user-mail-address' for the SMTP MAIL FROM envelope.
(smtpmail-via-smtp): Ditto.

etc/NEWS

@@ -1403,6 +1403,10 @@ If you had that set, you need to put
 
 in your ~/.authinfo file instead.
 
+*** SMTPmail defaults to using the address in the From: header as the
+SMTP MAIL FROM envelope.  To override this, set `mail-envelope-from'
+to the address you wish to use instead.
+
 ** SQL mode
 
 *** New options `sql-port', `sql-connection-alist', `sql-send-terminator',

lisp/ChangeLog

+2012-09-04  Lars Ingebrigtsen  <larsi@gnus.org>
+
+	* mail/smtpmail.el (smtpmail-send-it): Prefer the From: header
+	over `user-mail-address' for the SMTP MAIL FROM envelope.
+	(smtpmail-via-smtp): Ditto.
+
 2012-09-04  Dmitry Gutov  <dgutov@yandex.ru>
 	* progmodes/ruby-mode.el: Clean up keybindings.

lisp/mail/smtpmail.el

@@ -200,10 +200,10 @@ The list is in preference order.")
 	;; local binding in the mail buffer will take effect.
 	(smtpmail-mail-address
          (or (and mail-specify-envelope-from (mail-envelope-from))
-             (smtpmail-user-mail-address)
-	     (let ((from (mail-fetch-field "from")))
+             (let ((from (mail-fetch-field "from")))
 	       (and from
-		    (cadr (mail-extract-address-components from))))))
+		    (cadr (mail-extract-address-components from))))
+	     (smtpmail-user-mail-address)))
 	(smtpmail-code-conv-from
 	 (if enable-multibyte-characters
 	     (let ((sendmail-coding-system smtpmail-code-conv-from))
@@ -653,12 +653,10 @@ Returns an error if the server cannot be contacted."
 	 (or smtpmail-mail-address
 	     (and mail-specify-envelope-from
 		  (mail-envelope-from))
-	     (smtpmail-user-mail-address)
-	     ;; Fall back on the From: header as the envelope From
-	     ;; address.
 	     (let ((from (mail-fetch-field "from")))
 	       (and from
-		    (cadr (mail-extract-address-components from))))))
+		    (cadr (mail-extract-address-components from))))
+	     (smtpmail-user-mail-address)))
 	response-code
 	process-buffer
 	result