[Dovecot] Error - Dovecot Permission denied

[kbajwa]

Hello:

Since I posted this original messages, I have installed, re-installed
Postfix-2.3.3, Dovecot-1.1.1 & Dovecot-Sieve-1.1.5 over and over & still got
the "Permission Denied" error (see "/var/log/maillog" logs below).

Here what I found! If I add the following in "/etc/postfix/main.cf";

Mailbox_command = /usr/libexec/dovecot/deliver

Then the "Permission Denied" error appears and all mail is bounced back with
error message.

If I remove this line, all emails are delivered fine. No error.

This problem started when I switched dovecot from Ver# 1.0.7 to 1.1.1

So my question is: 

(1) has something changed in Dovecot V# 1.1.1 to cause this error?
(2) what if I leave this line out? Would it cause problem with either
Dovecot or Dovecot-Sieve?
(3) Any other solution.

FYI, I have already included Postfix, Dovecot & Dovecot-Sieve configuration
in my previous post.

HELP. I have spent 20 days on this problem.

Kirti


-------------------------------

Jul 27 09:12:48 www dovecot: Dovecot v1.1.2 starting up
Jul 27 09:12:49 www postfix/postfix-script: starting the Postfix mail system
Jul 27 09:12:49 www postfix/master[4948]: daemon started -- version 2.3.3,
configuration /etc/postfix

Jul 27 09:16:23 www postfix/smtpd[5613]: warning: 12.179.81.11: hostname
mail.greaterlink.net verification failed: Name or service not known
Jul 27 09:16:23 www postfix/smtpd[5613]: connect from unknown[12.179.81.11]
Jul 27 09:16:23 www postfix/smtpd[5613]: E31DA41C0028:
client=unknown[12.179.81.11]
Jul 27 09:16:24 www postfix/cleanup[5617]: E31DA41C0028:
message-id=<614A512260124AD1BF7288DB1ED46CE2 at Sunshine>
Jul 27 09:16:24 www postfix/qmgr[4967]: E31DA41C0028:
from=<kbajwa at tibonline.net>, size=860, nrcpt=1 (queue active)
Jul 27 09:16:24 www postfix/smtpd[5613]: disconnect from
unknown[12.179.81.11]


Jul 27 09:16:24 www postfix/local[5623]: E31DA41C0028:
to=<test at wildpeacockstudios.com>, relay=local, delay=0.99,
delays=0.74/0.03/0/0.22, dsn=5.3.5, status=bounced (local configuration
error. Command output: Fatal: open(/etc/dovecot.conf) failed: Permission
denied )

Jul 27 09:16:24 www postfix/cleanup[5617]: B73C441C002A:
message-id=<20080727151624.B73C441C002A at mail.wildpeacockstudios.com>
Jul 27 09:16:24 www postfix/qmgr[4967]: B73C441C002A: from=<>, size=2862,
nrcpt=1 (queue active)
Jul 27 09:16:24 www postfix/bounce[5626]: E31DA41C0028: sender non-delivery
notification: B73C441C002A
Jul 27 09:16:24 www postfix/qmgr[4967]: E31DA41C0028: removed
Jul 27 09:16:26 www postfix/smtp[5627]: B73C441C002A:
to=<kbajwa at tibonline.net>, relay=mail.tibonline.net[12.179.81.11]:25,
delay=1.4, delays=0.01/0.03/0.61/0.72, dsn=2.0.0, status=sent (250 OK)
Jul 27 09:16:26 www postfix/qmgr[4967]: B73C441C002A: removed