Sending mail no longer works

[Al Arduengo]

I am getting very frustrated.  In the past I have used Gnus sucessfully
for a long time with no issues until now.  I recently reinstalled
Slackare 10 and gnus/xemacs and now find that I cannot send mail. 
Sometimes it just hangs and I get everything I try to send in the
sendmail queue but it never leaves.  I *can* send news posts.  All other
mail programs I have tried *can* send mail.  I have read and tinkered
with all variables related to mail I can find to no avail.  So I will
take this approach. I will list my system's specs and hope that someone
will be able to tell me what to put in my .gnus/custom.el to get this
working again.

Slackware 10
Xemacs (or even Emacs for that matter)
Gnus 5.10.6

My nntp server requires authorization
My smtp server requires authorization
I have .authinfo set up
I don't care how I send mail (smtp-send-it or sendmail-send-it)
My machine name is exal
I don't know or care what my domain is (SBC DSL is my provider)

Can anyone please help?

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