[Dovecot] TLS / Dovecot / POP3

[John Espiro]

I am using Thunderbird 2.x as my client, Dovecot on the server (POP3 not
IMAP).

Currently I have in my conf file:

 protocols = pop3s pop3
 ssl_disable = no
 ssl_cert_file = /usr/share/ssl/certs/dovecot.pem
 ssl_key_file = /usr/share/ssl/private/dovecot.pem
 ssl_parameters_file = /var/run/dovecot/ssl-parameters.dat
 disable_plaintext_auth = yes
 login = pop3

In Thunderbird, I have the email server setup to:
 - Port 110
 - TLS

Here's my question:

If I change  protocols = pop3s pop3 to  protocols = pop3s I can no
longer connect to my mail server via Thunderbird unless I setup
Thunderbird to use SSL.

Am I doing something wrong?

Thanks,
John