smptmail.el authentication required

[Duane Winner]

I hope somebody can help me with this -- I've pulled all my hair out the 
 past week.

I am attempting to use smtpmail.el with authentication so that I can 
send messages to an smtp server that requires authentication. I've tried 
two different smtp servers that require authentication with which I have 
an account: ipostoffice.worldnet.att.net (ssl port 465 via stunnel) and 
smtp.comcast.net (ssl optional - I've tried both plain 25 and 465 thru 
stunnel).

In all cases, this is the debug output of my attempt:

"Sending failed; SMTP protocol error" ---- trace:

220 comcast.net - Maillennium ESMTP/MULTIBOX sccrmhc13 #4^M
EHLO fatalbert.heyheyhey.net^M
250-comcast.net^M
250-7BIT^M
250-8BITMIME^M
250-AUTH CRAM-MD5 LOGIN PLAIN^M
250-DSN^M
250-EXPN^M
250-HELP^M
250-NOOP^M
250-PIPELINING^M
250-SIZE 10485760^M
250-STARTTLS^M
250-VERS V04.80c++^M
250 XMVP 2^M
MAIL FROM: <duanewinner@comcast.net> SIZE=97^M
530 Authentication required^M
QUIT^M
221 comcast.net^M

But here is my .emacs info:

(load-library "smtpmail")
(setq send-mail-function 'smtpmail-send-it)
(setq user-full-name "My Name")
(setq user-mail-address "myaccountname@comcast.net")
(setq smtpmail-smtp-server "smtp.comcast.net")
(setq smtpmail-smtp-service 25)
(setq smtpmail-auth-credentials
      '(("smtp.comcast.net" 25 "myaccountname" "xxxxxxxx")))
(setq smtpmail-local-domain nil)


Why am I not authenticating? I have also tried changing my port #'s to 
465 and set up stunnel connections to get to the servers via stunnel. 
But no matter what, I alwasy get the 'Authentication required' error.

Any help on this would be greatly apprectiated.

I am running:
GNU Emacs 21.3.1 (i36-freebsd, X toolkit, Xaw3d scroll bars) of 2004-08-04

I have also tried to replace the sendmail.el with the 'latest version' 
from gnu.org dated 10/11/04.

Thanks,

Duane Winner
duanewinner@att.net