[Dovecot] FAQ: setting thunderbird to talk to dovecot

[Mauricio Tavares]

Let's say I have a postfix box, named mail.thespider.com, which is
setup to handle virtual mailbox domains. One of these domains will
handle is, thespider.com, and my email address in that domain is
boris at thespider.com. As I setup dovecot, I can telnet to the pop3 port
(110) and test it by logging in as boris at thespider.com (I would try
the imap port but I do not know how to login to imap from the telnet
prompt):

[raub at taz ~]$ telnet mail.thespider.com 110
Trying 192.168.1.12...
Connected to mail.thespider.com (192.168.1.12).
Escape character is '^]'.
+OK dovecot ready.
user boris at thespider.com
+OK
pass creepycrawly
+OK Logged in.
quit
+OK Logging out.
Connection closed by foreign host.
[raub at taz ~]$

How would I do the same under thunderbird from a machine in the same
lan (taz.thespider.com)? It seems to keep trying to login as
boris at mail.thespider.com, which will not fly.