[Dovecot] Help connecting from remote client (no auth attempts)

[Blake McBride]

Greetings,

I am running 64 bit Ubuntu server 10.04.04, postfix 2.7.0, and dovecot
1.2.9.  I installed the dovecot-postfix package so the two would be
configured to work together.

>From localhost I can send and receive email to/from arbitrary remote sites
without any problems.

I wish to send & receive email from my (remote) desktop via
Thunderbird through that sever.

When I attempt to configure Thunderbird I get the following on mail.log:

Mar 26 15:04:51 booklion dovecot: imap-login: Aborted login (no auth
attempts): rip=74.179.230.177, lip=192.168.168.53
Mar 26 15:04:51 booklion dovecot: last message repeated 2 times
Mar 26 15:04:51 booklion dovecot: pop3-login: Aborted login (no auth
attempts): rip=74.179.230.177, lip=192.168.168.53
Mar 26 15:04:51 booklion dovecot: last message repeated 3 times
Mar 26 15:04:51 booklion dovecot: imap-login: Aborted login (no auth
attempts): rip=74.179.230.177, lip=192.168.168.53
...

For now, I just want to control access through the normal passwd/shadow
mechanism.

I set in dovecot.conf:

disable_plaintext_auth = no
ssl = yes
passdb shadow {
}
userdb passwd {
}

I don't know what else to try.  Help would really be appreciated.

Blake McBride