@lisp
(setq message-send-mail-function 'smtpmail-send-it
smtpmail-default-smtp-server "YOUR SMTP HOST")
+;; The following variable needs to be set because of the FLIM version of
+;; smtpmail.el. Which smtpmail.el is used depends on the `load-path'.
+(setq smtp-default-smtp-server "YOUR SMTP HOST")
@end lisp
To the thing similar to this, there is @code{message-smtpmail-send-it}.