trouble sending email: smtp/startls/gnutls

["Timothy W. Hilton" <timothy.w.hilton@gmail.com>]

Hello,

I am able to read IMAP mail in gnus from several servers without a
problem.  I am having a lot of trouble sending mail, though, using
authsmtp through either TLS or SSL.

The relevant section of my .gnus is set up like this:
---------
(require 'smtpmail)

(setq starttls-use-gnutls t
      starttls-gnutls-program "gnutls-cli")

(setq send-mail-function 'smtpmail-send-it
      message-send-mail-function 'smtpmail-send-it)
(setq smtpmail-default-smtp-server "smtp.unm.edu"
      smtpmail-smtp-server "smtp.unm.edu"
      smtpmail-smtp-service 465 )
      smtpmail-starttls-credentials '(("smtp.unm.edu" 465 nil nil))
      smtpmail-debug-info t
      smtpmail-auth-credentials '(("smtp.unm.com" 465 "hilton" nil)))
---------

I've tried both starttls and gnutls; in both cases I get to 
Opening STARTTLS connection to `smtp.unm.edu:465'...done

and then eventually the connection times out.

It seems like my problem is similar to this:
http://groups.google.com/group/gnu.emacs.gnus/browse_thread/thread/d7ff2cda9096cb82
and
http://groups.google.com/group/gnu.emacs.gnus/browse_thread/thread/b1512f73190714f0?pli=1

I've tried everything I can glean from those threads to no avail.

I am able to open a connection using gnutls-cli:

--------

$gnutls-cli --port 465 smtp.unm.edu
Resolving 'smtp.unm.edu'...
Connecting to '129.24.170.25:465'...
- Certificate type: X.509
 - Got a certificate list of 2 certificates.

 - Certificate[0] info:
 # The hostname in the certificate matches 'smtp.unm.edu'.
 # valid since: Mon Jul 25 18:00:00 MDT 2011
 # expires at: Wed Aug  1 17:59:59 MDT 2012
 # fingerprint: AF:C5:14:BB:4E:6A:12:67:9E:65:D0:3A:1E:ED:E3:DF
 # Subject's DN: C=US,ST=New Mexico,L=Albuquerque,O=The University of New Mexico,OU=CIRT,CN=smtp.unm.edu
 # Issuer's DN: C=US,O=Thawte\, Inc.,CN=Thawte SGC CA - G2

 - Certificate[1] info:
 # valid since: Wed May 12 18:00:00 MDT 2004
 # expires at: Mon May 12 17:59:59 MDT 2014
 # fingerprint: 84:84:03:56:10:85:53:ED:9A:CA:60:B5:FA:99:D3:31
 # Subject's DN: C=ZA,O=Thawte Consulting (Pty) Ltd.,CN=Thawte SGC CA
 # Issuer's DN: C=US,O=VeriSign\, Inc.,OU=Class 3 Public Primary Certification Authority


- Peer's certificate issuer is unknown
- Peer's certificate is NOT trusted
- Version: TLS 1.0
- Key Exchange: RSA
- Cipher: 3DES 168 CBC
- MAC: SHA
- Compression: NULL
- Handshake was completed

- Simple Client Mode:

220 borealis.unm.edu ESMTP CommuniGate Pro 5.2.20
QUIT
221 borealis.unm.edu CommuniGate Pro SMTP closing connection
- Peer has closed the GNUTLS connection

--------

Is the unknown issuer/untrusted certificate comment above a problem?
I'm new at this and I'm getting to wit's end; I'd greatly appreciate any
advice!

Thanks!
Tim