changing smtp server?

[someusernamehere <someusernamehere@gmail.com>]

Hey I have this on my .gnus file:
;; function that change between smtp servers

(defun fs-change-smtp ()
  "Change the SMTP server according to the current from line."
  (save-excursion
    (let ((from
           (save-restriction
             (message-narrow-to-headers)
             (message-fetch-field "from"))))
      (message "From is `%s', setting `smtpmail-smtp-server' to `%s'"
               from
               (cond
                ((string-match "foo@bar.org" from)
                  ;; Use stmp-auth
                  (message "Using smtp-auth")
                   ;; Sending mail
                   ((....................
                      ....................))

                  ;; Use other server
                  (message "Using other server")
                 ((.......................
                   .......................))


                (t
                  (error
                     (concat "Don't know which mail server to use for
"
                               from))))))))

   ; (add-hook 'message-setup-hook 'fs-change-smtp)