dovecot - Feb 2010 - LMTP-Server: missing headers

Hello,

I just installed dovecot2-beta2 and configured the lmtp-server + postfix (no
virtual users)

postfix:
mail_version = 2.7-20100117
mailbox_transport = lmtp:unix:lmtp-server
lmtp_assume_final = yes

dovecot:
service lmtp {
  executable = lmtp
  protocol = lmtp
  unix_listener /var/spool/postfix/lmtp-server {
    group = postfix
    mode = 0660
    user = postfix
  }
}

Mail gets delivered to ~user/Maildir/
Feb  1 06:57:39 testhost dovecot: lmtp(8238): Connect from local
Feb  1 06:57:39 testhost postfix/lmtp[8237]: 07108A3608: to=<sca at
testhost.example.org>, orig_to=<root>,
relay=testhost.example.org[lmtp-server], delay=0.67, delays=0.22/0.03/0.22/0.2,
dsn=2.0.0, status=sent (250 2.0.0 <sca at testhost.example.org>
lwjfEVNtZksuIAAA4eG3hw Saved)
Feb  1 06:57:39 testhost dovecot: lmtp(8238, sca at testhost.example.org):
lwjfEVNtZksuIAAA4eG3hw: msgid=<20100201055739.07108A3608 at
testhost.example.org>: saved mail to INBOX

Second try: postfix using deliver
postfix:
mailbox_command = /usr/lib/dovecot/deliver

log:
Feb  1 07:21:08 testhost dovecot: lda(sca): msgid=<20100201062108.0D6D6A3608
at testhost.example.org>: saved mail to INBOX
Feb  1 07:21:08 testhost postfix/local[10039]: 0D6D6A3608: to=<sca at
testhost.example.org>, orig_to=<sca>, relay=local, delay=0.13,
delays=0.04/0.01/0/0.08, dsn=2.0.0, status=sent (delivered to command:
/usr/lib/dovecot/deliver)

In the first case there are *no* Return-Path and Delivered-To Headers.
In the (most common) second case the *are* present.
Why these Headers are not included while using the LMTP-Server?

-- 
Andreas Schulze
Internetdienste | P532

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On 1.2.2010, at 8.38, Andreas Schulze wrote:
> In the first case there are *no* Return-Path and Delivered-To Headers.
> In the (most common) second case the *are* present.
> Why these Headers are not included while using the LMTP-Server?
I guess I could add Return-Path header. I could also add Delivered-To as long as
there is only a single recipient, but adding it for multiple recipients would
make everything much more difficult than I'd like.

I was wondering about Delivered-To header before too. What do people use it for?