[Dovecot] chroot lmtp, then can not open /usr/local/lib/dovecot

[johnw]

On Mon, 06 Jun 2011 17:46:31 +0300, Timo Sirainen wrote:
> On Sat, 2011-06-04 at 21:48 +0800, johnw wrote:
>> i want to chroot lmtp with sieve, but have some problem, look like 
>> lmtp
>> can not load sieve's lib or something.
>> the error message like this:
>>
>> dovecot: lmtp(12799): Fatal: opendir(/usr/local/lib/dovecot) failed: 
>> No
>> such file or directory
>>
>> all is work fine, when not config lmtp chroot.
>> can i config lmtp load sieve before chroot?
>
> Not currently. Or you could put the sieve plugin inside the chroot 
> (and
> maybe change protocol lmtp { mail_plugins_dir }).

after copy those sieve's thing to chroot_dir, and link the userdb 
socket to chroot_dir.
i see the error like this:

(lmtp) Couldn't drop privileges: Process is already chrooted, can't 
un-chroot for this user

i already config mail_chroot, should i remove it?(mail_chroot)
any how-to document is for lmtp chroot?

please help, and thank you.