authenticate at smtp server

[Norbert Kaufmann]

I am using the following configuration - cut and pasted from 
http://josefsson.org/smtpmail.html.


;; If you use the default mail user agent.
(setq send-mail-function 'smtpmail-send-it)
;; If you use Message or Gnus.
(setq message-send-mail-function 'smtpmail-send-it)
(setq smtpmail-default-smtp-server "auth.mail.onlinehome.de")
(setq smtpmail-smtp-server "auth.mail.onlinehome.de")
;;(setq smtpmail-auth-credentials
;;     '(("auth.mail.onlinehome.de" 25 "username" "secret")))
(setq smtpmail-starttls-credentials
           '(("auth.mail.onlinehome.de" 25 "username" secret)))
(setq smtpmail-debug-info t)
(setq smtpmail-debug-verb t)


but i am not able to send mail. Here is the trace.

220 mrelayng.kundenserver.de ESMTP Thu, 25 Dec 2003 18:01:59 +0100
EHLO clarence.hal
250-mrelayng.kundenserver.de Hello clarence.hal [80.131.141.219]
250-SIZE 20971520
250-PIPELINING
250-AUTH=PLAIN LOGIN
250-AUTH PLAIN LOGIN
250-STARTTLS
250 HELP
MAIL FROM: <norbert@akumakun.de> SIZE=90
530 Authentication required
QUIT
221 mrelayng.kundenserver.de closing connection

emacs version 21.2.1

Can please somebody give me a hint?

TIA

Norbert