I have setup Postfix and Dovecot on an Ubuntu box following the instructions

http://www.exratione.com/2012/05/a-mailserver-on-ubuntu-1204-postfix-dovecot-mysql/

I can see that email is being delivered to and accepted by the server, but the email is not available for retrieval via POP3. What could be missing in my configuraton? It seems that email is not being properly handed off to Dovecot.

Here are what I believe are the relevant /var/log/mail.log entries for an attempt to send email from another domain (hosted by Gmail) to the domain I have setup:

Logged during SMTP connection

postfix/smtpd[14689]: connect from mail-vb0-f50.google.com[209.85.212.50]
postfix/smtpd[14689]: Anonymous TLS connection established from mail-vb0-f50.google.com[209.85.212.50]: TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)
postfix/smtpd[14689]: 5782740ACF: client=mail-vb0-f50.google.com[209.85.212.50]
postfix/cleanup[14696]: 5782740ACF: message-id=<CAEjmKcjHnTY4yk=3QXoNrD76=04g-s9utPguTFB02Fx53GMPmw@mail.gmail.com>
postfix/qmgr[14687]: 5782740ACF: from=<[email protected]>, size=1947, nrcpt=1 (queue active)
postfix/smtpd[14702]: connect from mail.destinationdomain.com[127.0.0.1]
postfix/smtpd[14702]: 2940A41AA9: client=mail.destinationdomain.com[127.0.0.1]
postfix/cleanup[14696]: 2940A41AA9: message-id=<CAEjmKcjHnTY4yk=3QXoNrD76=04g-s9utPguTFB02Fx53GMPmw@mail.gmail.com>
postfix/qmgr[14687]: 2940A41AA9: from=<[email protected]>, size=2450, nrcpt=1 (queue active)
amavis[21309]: (21309-02) Passed CLEAN, [209.85.212.50] <[email protected]> -> <[email protected]>, Message-ID: <CAEjmKcjHnTY4yk=3QXoNrD76=04g-s9utPguTFB02Fx53GMPmw@mail.gmail.com>, mail_id: W52ZB8FAAA+8, Hits: -0.101, size: 1946, queued_as: 2940A41AA9, [email protected], 784 ms
postfix/smtpd[14702]: disconnect from mail.destinationdomain.com[127.0.0.1]
postfix/smtp[14698]: 5782740ACF: to=<[email protected]>, relay=127.0.0.1[127.0.0.1]:10024, delay=1.1, delays=0.29/0.01/0/0.79, dsn=2.0.0, status=sent (250 2.0.0 from MTA([127.0.0.1]:10025): 250 2.0.0 Ok: queued as 2940A41AA9)
postfix/qmgr[14687]: 5782740ACF: removed
dovecot: lda([email protected]): msgid=<CAEjmKcjHnTY4yk=3QXoNrD76=04g-s9utPguTFB02Fx53GMPmw@mail.gmail.com>: saved mail to INBOX
postfix/pipe[14703]: 2940A41AA9: to=<[email protected]>, relay=dovecot, delay=0.08, delays=0.02/0.02/0/0.04, dsn=2.0.0, status=sent (delivered via dovecot service)
postfix/qmgr[14687]: 2940A41AA9: removed

Logged during POP3 retrieval attempts

dovecot: pop3-login: Login: user=<[email protected]>, method=PLAIN, rip=209.85.220.135, lip=10.195.83.10, mpid=14706
dovecot: pop3([email protected]): Disconnected: Logged out top=0/0, retr=1/2557, del=1/1, size=2540
postfix/smtpd[14689]: disconnect from mail-vb0-f50.google.com[209.85.212.50]
dovecot: pop3-login: Login: user=<[email protected]>, method=PLAIN, rip=209.85.212.31, lip=10.195.83.10, mpid=14708
dovecot: pop3([email protected]): Disconnected: Logged out top=0/0, retr=0/0, del=0/0, size=0