This is a followup on a thread back on roundup-users back in April about an auth error
with gmail smtp. The error looks like:

Traceback (most recent call last):
 File "/usr/lib/python2.5/site-packages/roundup/scripts/roundup_server.py",
line 188, in run_cgi
   self.inner_run_cgi()
 File "/usr/lib/python2.5/site-packages/roundup/scripts/roundup_server.py",
line 362, in inner_run_cgi
   tracker.Client(tracker, self, env).main()
 File "/usr/lib/python2.5/site-packages/roundup/cgi/client.py", line
252, in main
   self.inner_main()
 File "/usr/lib/python2.5/site-packages/roundup/cgi/client.py", line
383, in inner_main
   self.mailer.exception_message()
 File "/usr/lib/python2.5/site-packages/roundup/mailer.py", line 171,
in exception_message
   self.standard_message(to, subject, content)
 File "/usr/lib/python2.5/site-packages/roundup/mailer.py", line 104,
in standard_message
   self.smtp_send(to, message)
 File "/usr/lib/python2.5/site-packages/roundup/mailer.py", line 200,
in smtp_send
   raise MessageSendError("Error: SMTPConnection couldn't send email:
%s" %msg )
MessageSendError: Error: SMTPConnection couldn't send email: SMTP AUTH
extension not supported by server.

This is with tls = yes (gmail SMTP requires tls).

The original reporter included a non-failing test-case for smtplib
with which I was able to make a simple patch:

(roundup)eric@Newsvetter:~/sites/trackers$ diff -u mailer.py  mailer2.py
--- mailer.py   2009-01-04 02:40:40.000000000 +0000
+++ mailer2.py  2009-01-04 02:40:58.000000000 +0000
@@ -208,6 +208,7 @@
                              local_hostname=config['MAIL_LOCAL_HOSTNAME'])
        # start the TLS if requested
        if config["MAIL_TLS"]:
+            self.ehlo()
            self.starttls(config["MAIL_TLS_KEYFILE"],
                config["MAIL_TLS_CERTFILE"])

The patch fixes the error for me.