[Dovecot] Problem setting up dovecot on Debian: "telnet: Unable to connect to remote host: Connection refused"

[Chris Evans]

I would like to get dovecot running on my laptop so I can transfer a lot 
of old Email from Thunderbird mailbox files to a hosted zimbra service. 
  However I'm falling at the first hurdle.  I'm running Debian squeeze 
i386 (kernel 2.6.32-5-686) and have installed dovecot-imapd and 
dovecot-common with synaptic and edited /etc/dovecot/dovecot.conf to 
make sure it has the right protocols and listen instructions.  Here's 
dovecot -n

root at delldeb:/etc/dovecot# dovecot -n
# 1.2.15: /etc/dovecot/dovecot.conf
# OS: Linux 2.6.32-5-686 i686 Debian 6.0.6
log_timestamp: %Y-%m-%d %H:%M:%S
listen: 143 993
disable_plaintext_auth: no
login_dir: /var/run/dovecot/login
login_executable: /usr/lib/dovecot/imap-login
mail_privileged_group: mail
mbox_write_locks: fcntl dotlock
auth default:
   passdb:
     driver: pam
   userdb:
     driver: passwd

Here's ps:

root at delldeb:/etc/dovecot# ps aux | grep dove
root     10353  0.0  0.0   3944   792 ?        Ss   15:32   0:00 
/usr/sbin/dovecot -c /etc/dovecot/dovecot.conf
root     10356  0.0  0.0  10008  2420 ?        S    15:32   0:00 
dovecot-auth
root     10360  0.0  0.0  10008  2372 ?        S    15:32   0:00 
dovecot-auth -w
dovecot  10361  0.0  0.0   5412  2024 ?        S    15:32   0:00 imap-login
dovecot  10362  0.0  0.0   5412  2024 ?        S    15:32   0:00 imap-login
dovecot  10363  0.0  0.0   5412  2028 ?        S    15:32   0:00 imap-login
root     10393  0.0  0.0   3304   772 pts/2    S+   15:33   0:00 grep dove


Here's netstat:
root at delldeb:/etc/dovecot# netstat -tap | grep 143
tcp        0      0 0.0.0.143:imap2         *:* 
LISTEN      9178/dovecot
tcp        0      0 0.0.0.143:imaps         *:* 
LISTEN      9178/dovecot

I can telnet into SMTP OK with telnet localhost 25 but telnet localhost 
143 gets me the "Connection refused" message.  I've changed auth_debug 
to "yes" and now /var/log/mail.info says:

Jan  5 15:32:13 delldeb dovecot: Dovecot v1.2.15 starting up (core dumps 
disabled)
Jan  5 15:32:14 delldeb dovecot: auth(default): new auth connection: 
pid=10361
Jan  5 15:32:14 delldeb dovecot: auth(default): new auth connection: 
pid=10362
Jan  5 15:32:14 delldeb dovecot: auth(default): new auth connection: 
pid=10363

That doesn't change after I try the telnet login again so I think that's 
just telling me that the dovecot daemon started and launched it's 
listeners (but I know I don't know how to read this so correction welcome).

My reading of all of this is that the dovecot daemon is up and running, 
that it's listening correctly on 143 and 993 and that I have to do 
something else to get authorisation even to start the IMAP dialogue with 
the server. I would like to get it working and locked to SSL only but 
thought I should start with both unencrypted and encrypted.

Can someone help me or point me to the bits of documentation or good web 
howto or the like that I've missed?

TIA,

Chris (long term Debian user but it's some years since I last ran my own 
mail server and I'm a total newby to imap and dovecot)