[Evolution] Configuring evolution with Linux email server problems

[Leonard Evens <len math northwestern edu>]

I have a small local network at home with Linux and XP systems attached
to it.  I also have a computer in my office at school, which I manage
myself, which I had set up as a mail server, both for incoming and
outgoing mail.  I used evolution as my linux mail agent.

At a certain point comcast, my ISP at home, started blocking port 25
which meant that my outgoing mail failed.  So I switched to using port
587 with comcast's outgoing mail server, but continued too use my office
computer for an incoming mail server.

I would now like to switch back, but I am having troubles.  I managed to
figure out how to configure sendmail.mc on my office computer to tell it
to use port 587.   

But I can't get outgoing mail to work however I configure evolution on
my home computer
I've tried various things but none seem to work.  the closest I've come
is that I get a request for an SMTP password for me as user on the
office host, but that returns with
"Unable to authenticate to SMTP server.
Bad authentication response from server."
and a request to enter the password again.

With other choices, it just hangs and when I cancel it.
/var/log/maillog on the office server shows
"did not issue MAIL/EXPN/VRFY/ETRN during connection to MSA"
which I believe is harmless, just telling me that no thing was done, but
not the reason why.

I've tried  to see what  happens if iptables on the server is turned
off, and it makes no difference.

It has something to do with either evolution's configuration for sending
email or with something on my office server,  but I can't see what.  I
repat that at one point I did have this working with the office server
when it was using prot 25.

Of course, a complete solution to my problem would be appreciated, but
even a hint of how to go about troubleshooting the problem would be
helpful.

Meanwhile. I've gone back to using comcast's outgoing mail server.

P.S.  I can telnet to the server to port 587, but I don't know what to
do next to try   to see what is wrong.  /var/log/maillog has offered
little help.