[Dovecot] Temporary Failures

2011-10-22 Thread Jack Fredrikson
Hi;
I keep getting errors like this one:

Oct 22 16:51:08 example postfix/pipe[12021]: C2F705790169: 
to=, relay=dovecot, delay=2.1, delays=2/0.01/0/0.08, 
dsn=4.3.0, status=deferred (temporary failure. Command output: doveconf: 
Warning: NOTE: You can get a new clean config file with: doveconf -n > 
dovecot-new.conf doveconf: Warning: Obsolete setting in 
/usr/local/etc/dovecot/dovecot.conf:5: imap_client_workarounds=outlook-idle is 
no longer necessary doveconf: Warning: Obsolete setting in 
/usr/local/etc/dovecot/dovecot.conf:17: add auth_ prefix to all settings inside 
auth {} and remove the auth {} section completely doveconf: Warning: Obsolete 
setting in /usr/local/etc/dovecot/dovecot.conf:19: passdb pam {} has been 
replaced by passdb { driver=pam } doveconf: Warning: Obsolete setting in 
/usr/local/etc/dovecot/dovecot.conf:21: userdb passwd {} has been replaced by 
userdb { driver=passwd } doveconf: Warning: Obsolete setting in 
/usr/local/etc/dovecot/dovecot.conf:23: auth_user has
 been replaced by service auth { user } doveconf:


Why don't they get delivered? Also, I've tried to follow the advice in the 
warnings and it never works. I've tried the doveconf -n > dovcot-new.conf 
command and the same conf file I've been using pops up. Can someone post some 
code that reflects how the new conf file should look?
TIA,
Jack

[Dovecot] off topic question

2011-10-22 Thread Spyros Tsiolis
 Hello list,

Is anybody out there who knows of an MTA that can 

do LDAP writes ?
I apologize for bringing this to the list, however, I did
some googling and cannot find any answer to this.

Thank you all,

spyros

 

"I merely function as a channel that filters 
music through the chaos of noise"
- Vangelis


[Dovecot] setacl fails - does not find dovecot-acl file

2011-10-22 Thread Michael Stilkerich

Hi,

  I'm using dovecot 2.0.13 that ships with Ubuntu 11.10.
I tried setting up a shared namespace as documented in the wiki to 
enable the sharing of a mailbox between two users.


I have a Maildir(++) directory for each user. Each user has a system 
account. The Maildir of each user is owned by the user's system account

and group read/writable by the group mail (hence mail_access_groups=mail).

Relevant parts of my config:

mail_plugins = acl
mail_location = maildir:/home/dovecot/%u
mail_access_groups = mail

namespace {
  type = private
  separator = /
  prefix =
  inbox = yes
  hidden = no
  subscriptions = yes
}
namespace {
  type = shared
  separator = /
  prefix = shared/%%u/
  location = maildir:/home/dovecot/%%u:INDEX=/home/dovecot/%u/shared/%%u
  subscriptions = no
  list = children
}

protocol imap {
  mail_plugins = $mail_plugins imap_acl
}

plugin {
  acl = vfile
}
plugin {
  acl_shared_dict = file:/home/dovecot/shared-mailboxes
}

When I try to create an ACL in a telnet session, the command fails with 
an internal error. The log shows:


dovecot: imap(michael): Error: 
fstat(/home/dovecot/michael/.test/dovecot-acl.lock) failed: No such file 
or directory
dovecot: imap(michael): Error: 
file_dotlock_open(/home/dovecot/michael/.test/dovecot-acl) failed: No 
such file or directory


The error occurs whether a (manually created) dovecot-acl file exists or 
not. The dovecot-acl.lock file is created by not removed afterwards.
Subsequent setacl commands will timeout waiting for the lock to be 
released until I delete it manually.


If I create the dovecot-acl file manually and provide access to another 
user, the getacl command will correctly show the permissions and the 
other user can access the folder. setacl will still fail to modify the 
acl file, however (same error).


Another thing that irritates me is that dovecot seems to use the dotlock 
locking method, although I explicitly set lock_method to

fcntl (also tried flock, same behavior).

I'm not using chroot.

I appreciate any help to get this sorted out.

Thanks,
  Michael




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Description: S/MIME Cryptographic Signature


[Dovecot] Dovecot crashes totally

2011-10-22 Thread Gordon Grubert
Hello,

our dovecot server crashes totally without any really useful
log messages. The error log can be found in the attachment.
The only way to get dovecot running again is a complete
system restart.

Dovecot version: 2:2.0.15-0~auto+5
 (2.0.15 (6b7242ead6ed))
Configuration  : see attachment
OS : Debian Squeeze amd64
Dovecot source : http://xi.rename-it.nl/debian/ \
 stable-auto/dovecot-2.0 main

This problem has already occurred with the version 2.0.13
where the log says as few as the current logs :-(

Best regards,
Gordon
-- 
Leiter AG Technische Infrastruktur und Basisdienste
Universitaetsrechenzentrum (URZ)
E.-M.-Arndt-Universitaet Greifswald
Felix-Hausdorff-Str. 12
17489 Greifswald
Germany

Tel. +49 3834 86-1456
Fax. +49 3834 86-1401


# 2.0.15 (6b7242ead6ed): /etc/dovecot/dovecot.conf
# OS: Linux 2.6.32-5-amd64 x86_64 Debian 6.0.2 
auth_mechanisms = plain login
auth_username_translation = %Lu
auth_verbose = yes
default_client_limit = 12688
disable_plaintext_auth = no
mail_location = maildir:~/Maildir
mail_plugins = quota acl
managesieve_notify_capability = mailto
managesieve_sieve_capability = fileinto reject envelope encoded-character 
vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy 
include variables body enotify environment mailbox date ihave
namespace {
  inbox = yes
  list = yes
  location = 
  prefix = 
  separator = /
  subscriptions = yes
  type = private
}
namespace {
  list = children
  location = 
maildir:%%h/Maildir:INDEX=%h/Maildir/shared/%%u:CONTROL=%h/Maildir/shared/%%u
  prefix = shared/%%u/
  separator = /
  subscriptions = yes
  type = shared
}
passdb {
  args = /etc/dovecot/dovecot-ldap.conf
  driver = ldap
}
plugin {
  acl = vfile
  acl_shared_dict = file:/var/vmail/DOVECOT/shared-mailboxes
  quota = maildir
  quota_rule = *:storage=10G
  quota_warning = storage=95%% /usr/local/bin/QuotaWarning.pl 95 %n
  quota_warning2 = storage=90%% /usr/local/bin/QuotaWarning.pl 90 %n
  quota_warning3 = storage=80%% /usr/local/bin/QuotaWarning.pl 80 %n
  quota_warning4 = storage=70%% /usr/local/bin/QuotaWarning.pl 70 %n
  sieve = ~/.dovecot.sieve
  sieve_dir = ~/sieve
  sieve_max_redirects = 10
}
protocols = lmtp pop3 imap sieve
service auth {
  client_limit = 16884
  unix_listener /var/spool/postfix/public/dovecot {
group = postfix
mode = 0600
user = postfix
  }
  unix_listener auth-master {
group = vmail
mode = 0660
  }
  unix_listener auth-userdb {
group = vmail
user = vmail
  }
  user = root
}
service imap-login {
  process_min_avail = 16
  service_count = 0
}
service imap {
  process_limit = 8192
}
service lmtp {
  unix_listener /var/spool/postfix/public/lmtp-dovecot {
group = postfix
mode = 0660
user = postfix
  }
}
service managesieve-login {
  inet_listener sieve {
port = 4190
  }
  process_min_avail = 16
  service_count = 0
}
service pop3-login {
  process_min_avail = 16
  service_count = 0
}
service pop3 {
  process_limit = 8192
}
shutdown_clients = no
ssl = required
ssl_ca = Oct 11 09:55:23 mailserver2 dovecot: master: Error: service(imap): Initial 
status notification not received in 30 seconds, killing the process
Oct 11 09:56:23 mailserver2 dovecot: imap-login: Error: master(imap): Auth 
request timed out (received 0/12 bytes)
Oct 11 09:56:23 mailserver2 dovecot: imap-login: Error: master(imap): Auth 
request timed out (received 0/12 bytes)
[...]
Oct 11 09:57:08 mailserver2 dovecot: imap-login: Error: net_connect_unix(imap) 
failed: Resource temporarily unavailable
Oct 11 09:57:09 mailserver2 dovecot: imap-login: Error: net_connect_unix(imap) 
failed: Resource temporarily unavailable
[...]
Oct 11 10:20:14 mailserver2 dovecot: pop3-login: Error: net_connect_unix(pop3) 
failed: Resource temporarily unavailable
Oct 11 10:20:15 mailserver2 dovecot: imap-login: Error: net_connect_unix(imap) 
failed: Resource temporarily unavailable
Oct 11 10:20:15 mailserver2 dovecot: pop3-login: Error: net_connect_unix(pop3) 
failed: Resource temporarily unavailable
[...]
Oct 11 10:20:55 mailserver2 dovecot: pop3-login: Error: master(pop3): Auth 
request timed out (received 0/12 bytes)
Oct 11 10:20:55 mailserver2 dovecot: pop3-login: Error: master(pop3): Auth 
request timed out (received 0/12 bytes)
[...]
Oct 11 10:21:14 mailserver2 dovecot: pop3-login: Error: read(anvil) failed: EOF
Oct 11 10:21:14 mailserver2 dovecot: pop3-login: Error: read(anvil) failed: EOF





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Description: S/MIME Cryptographic Signature


[Dovecot] First Installation, Problems...

2011-10-22 Thread Jack Fredrikson
Hi;

[root@example jack]# /usr/local/sbin/dovecot --version
2.0.15

[root@example jack]# /usr/local/bin/doveconf -n
# 2.0.15: /usr/local/etc/dovecot/dovecot.conf
doveconf: Warning: NOTE: You can get a new clean config file with: doveconf -n 
> dovecot-new.conf
doveconf: Warning: Obsolete setting in /usr/local/etc/dovecot/dovecot.conf:5: 
imap_client_workarounds=outlook-idle is no longer necessary
doveconf: Warning: Obsolete setting in /usr/local/etc/dovecot/dovecot.conf:17: 
add auth_ prefix to all settings inside auth {} and remove the auth {} section 
completely
doveconf: Warning: Obsolete setting in /usr/local/etc/dovecot/dovecot.conf:21: 
passdb sql {} has been replaced by passdb { driver=sql }
doveconf: Warning: Obsolete setting in /usr/local/etc/dovecot/dovecot.conf:24: 
userdb sql {} has been replaced by userdb { driver=sql }
doveconf: Warning: Obsolete setting in /usr/local/etc/dovecot/dovecot.conf:27: 
userdb prefetch {} has been replaced by userdb { driver=prefetch }
doveconf: Warning: Obsolete setting in /usr/local/etc/dovecot/dovecot.conf:29: 
auth_user has been replaced by service auth { user }
# OS: Linux 2.6.18-028stab094.3 x86_64 CentOS release 5.4 (Final) vzfs
auth_mechanisms = plain login
mail_location = maildir:/var/vmail/%d/%u
passdb {
  args = /usr/local/etc/dovecot/sql.conf
  driver = sql
}
plugin {
  quota = maildir:storage=10240:messages=1000
  trash = /usr/local/etc/dovecot/trash.conf
}
service auth {
  unix_listener /var/run/dovecot/auth-master {
    group = mail
    mode = 0660
    user = vmail
  }
  unix_listener /var/spool/postfix/private/auth {
    group = mail
    mode = 0660
    user = postfix
  }
  user = nobody
}
ssl = no
userdb {
  args = /usr/local/etc/dovecot/sql.conf
  driver = sql
}
userdb {
  driver = prefetch
}
protocol imap {
  imap_client_workarounds = delay-newmail
  mail_plugins = quota imap_quota
}
protocol pop3 {
  mail_plugins = quota
  pop3_client_workarounds = outlook-no-nuls oe-ns-eoh
}
protocol lda {
  info_log_path = /var/log/dovecot-deliver.log
  log_path = /var/log/dovecot-deliver.log
  mail_plugins = quota
  postmaster_address = postmas...@creative.vi
}


It appears that I have postfix at least partially working:

postfix/pipe[5280]: 9FDE0579012F: to=, relay=spamfilter, delay=6, 
delays=3/0.01/0/3, dsn=2.0.0, status=sent (delivered via spamfilter service)

I don't know where it ended up :-} There's nothing in /var/vmail, the dovecot 
destination. This is true even before I set the postfix content_filter to 
spamassassin (when it said "delivered to Maildir" or some such). Please advise.

TIA,
Jack

Re: [Dovecot] Getting the SMTP envelope through IMAP?

2011-10-22 Thread Hadmut Danisch

> The mbox from-line, not to be confused with the From: header, is
> simply not part of the email message but used only as a separator.
> Heck, it need not even contain valid information, but only proper
> formatting to satisfy picky/"smart" MUA's. Usually, it conveniently
> does carry some useful information, but e.g. when the SMTP
> envelope-from is '<>' then the mbox from-line usually contains
> something like MAILER-DAEMON to stay within the formatting specification.

Once again: I've never asked for an explanation about what that
From-Line is.


I did not ask whether it contains useful information either.


I've asked whether dovecot allows to retrieve it over IMAP.


Why is it impossible for you to understand the question before answering?


> Most people do not want an answer to the question they asked, but want
> a solution to their problem. 

I did not ask for a solution of a problem, either.

I've asked for a precise answer exactly to the question I've asked.

That's why you fail to focus on the question and to answer it. Because
you want to sell your solution for what you believe the problem is - or
what you like it to be. But your assumption about the problem is
completely wrong. So is your answer.


Stop obtruding solutions that nobody has asked for.





Re: [Dovecot] Getting the SMTP envelope through IMAP?

2011-10-22 Thread Maarten Bezemer


On Sat, 22 Oct 2011, Hadmut Danisch wrote:


Again, this discussion is nuts. If this is supposed to be some support
mailing list (as the dovecot web page suggests) people should take care
to focus on the question rather than taking a question as an opportunity
for telling their individual opinion.


The main question is whether I can draw a precise copy of a mailfolder
through IMAP without any loss of data.


My last reply to this thread, then.

The answer to your main question would be 'yes', since Dovecot's IMAP 
interface supports retrieving the entire email message including all its 
meta-data (aka headers or envelope).


The mbox from-line, not to be confused with the From: header, is simply 
not part of the email message but used only as a separator.
Heck, it need not even contain valid information, but only proper 
formatting to satisfy picky/"smart" MUA's. Usually, it conveniently does 
carry some useful information, but e.g. when the SMTP envelope-from is 
'<>' then the mbox from-line usually contains something like MAILER-DAEMON 
to stay within the formatting specification.


So, instead of blaming others of derailing a discussion and/or not simply 
answering a question, it might be an equally good idea to think twice 
about how you asked the question.


I'm actually happy that 'simple' questions are handled the way they are. 
Most people do not want an answer to the question they asked, but want a 
solution to their problem. Which they may have described in the question 
but often is left as an exercise for the reader. ;-)



But then again, I'm a technician, not a shrink, so my apologies for being 
so unfriendly...



--
Maarten


Re: [Dovecot] setacl fails - does not find dovecot-acl file

2011-10-22 Thread Michael Stilkerich

Hi again,

On 22.10.2011 15:16, Michael Stilkerich wrote:


When I try to create an ACL in a telnet session, the command fails with
an internal error. The log shows:

dovecot: imap(michael): Error:
fstat(/home/dovecot/michael/.test/dovecot-acl.lock) failed: No such file
or directory
dovecot: imap(michael): Error:
file_dotlock_open(/home/dovecot/michael/.test/dovecot-acl) failed: No
such file or directory


 I found that the problem seems to be the try_create_lock_hardlink() 
function, which is used to create the lock file. I don't now why it
doesn't work, but if I modify the code of dotlock_create() to always use 
try_create_lock_excl() instead ignoring the setting of use_excl_lock in 
the dotlock_settings structure, it works just fine for me.


I noticed in the log that the issue not only occurs with the dovecot-acl 
files but with other files, too, namely the

dovecot.index.log and my acl_shared_dict file.

Looking at the static dotlock_settings structure in the acl-file 
backend, I don't see how its use_excl_lock could possible be set to 1 by 
the configuration (i.e., it doesn't seem that the dotlock_use_excl
configuration option is considered). For the maildirlock, an environment 
variable "DOTLOCK_USE_EXCL" is checked instead of the

config setting. I'm not sure whether it is intentional that the hardlink
variant is generally used in these cases.

-Michael



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Description: S/MIME Cryptographic Signature


Re: [Dovecot] Getting the SMTP envelope through IMAP?

2011-10-22 Thread Hadmut Danisch
On 22.10.2011 18:56, Maarten Bezemer wrote:
> On the other hand, the question was a bit broad as a starting point.
> The SMTP envelope is nothing more than SMTP protocol and is not in
> itself part of the email format RFC. If you want to have this
> information saved in the email message, then it is the task of the
> SMTP-server to add this in the headers of the message. (Hardly
> parseable in Received headers, probably better when also included in
> things like Return-path, Delivery-date and Envelope-to.)
> Whether or not one should apply any filtering, or when, or where, may
> be related to this topic but I'd say that's the freedom of the user.
> Or, the arbitrary choice of some manager ;-) 


Again, this discussion is nuts. If this is supposed to be some support
mailing list (as the dovecot web page suggests) people should take care
to focus on the question rather than taking a question as an opportunity
for telling their individual opinion.


The main question is whether I can draw a precise copy of a mailfolder
through IMAP without any loss of data.


It does not make any sense to discuss what that information could be
used for, especially nobody on that list is familiar with the local
requirements I have to fulfill.


(BTW, I am familiar with the SMTP envelope, I was working more than two
years at the IRTF and IETF about treatment of the SMTP envelope, and
doing mail system administration since around 1989. I don't need any
introduction or further discussion about that.)


Please understand that I do not want to waste any more time in this
discussion that completely misses the point and the initial question.




Re: [Dovecot] Getting the SMTP envelope through IMAP?

2011-10-22 Thread Maarten Bezemer


On Sat, 22 Oct 2011, Hadmut Danisch wrote:


I don't believe it does make much sense to ask technical questions if
this ends in silly discussions about whether an admin should do
something this or that way or how long logfiles should be kept. This is
not related to the technical question anymore and completely useless.

I was looking for a simple yes or no, not for fruitless debates.

I hate it if one is asking a pure technical question and in response
gets lessons in what people consider as a correct behaviour.


This is a generic problem with technicians, always having tons of 
arguments to support their statements ;-)


On the other hand, the question was a bit broad as a starting point. The 
SMTP envelope is nothing more than SMTP protocol and is not in itself part 
of the email format RFC. If you want to have this information saved in the 
email message, then it is the task of the SMTP-server to add this in the 
headers of the message. (Hardly parseable in Received headers, probably 
better when also included in things like Return-path, Delivery-date and 
Envelope-to.)
Whether or not one should apply any filtering, or when, or where, may be 
related to this topic but I'd say that's the freedom of the user. Or, the 
arbitrary choice of some manager ;-)



Just my 2 cents..

--
Maarten


Re: [Dovecot] Getting the SMTP envelope through IMAP?

2011-10-22 Thread Hadmut Danisch
I don't believe it does make much sense to ask technical questions if
this ends in silly discussions about whether an admin should do
something this or that way or how long logfiles should be kept. This is
not related to the technical question anymore and completely useless.

I was looking for a simple yes or no, not for fruitless debates.

I hate it if one is asking a pure technical question and in response
gets lessons in what people consider as a correct behaviour.




Re: [Dovecot] Getting the SMTP envelope through IMAP?

2011-10-22 Thread Dennis Guhl
On Sat, Oct 22, 2011 at 11:09:28AM +0200, Hadmut Danisch wrote:
> On 22.10.2011 10:15, Dennis Guhl wrote:
> >> It's required for debugging purposes, writing mail filters, create
> >> > blacklist filters from detected spam, etc.
> > Disregarding end users mail filters this are all tasks for mailadmins

^^^

> > which can tell thier MTA to write a reliable Return-Path: header and
> > which have access to the corresponding maillog.
> 
> Definitely wrong.
> 
> Writing mail filters like ~/.mailfilter is a user's task. Training their
> individual spam filters as well.

. o O (  at least he didn't truncate the relevant quote this time )

> And whether you're even permitted to keep the maillog that long depends
> on your local data protection laws.

How long do you think a responsible mailadmin need to train filter.

Btw. even here in Germany, where we most likely have the most
restrictive laws regarding the protection of personal data, I am
allowed to keep the maillog as long as I can show that the log is
needed to satisfy user requests.

> And neither the Return-Path nor the  Received-Lines reveal the precise
> date of delivery as the From line contains.

Nonsense.

Every RFC conformant received line contains the full date-time as
specified in RFC 5322. Nothing else is taken into account for the mbox
>From line.

Dennis


[Dovecot] Quota warning

2011-10-22 Thread nuno marques




Hi, I cant run quota warning or other script.
 any suggestions?  Oct 22 10:02:52 userseuac dovecot: imap(user4): Debug: 
Effective uid=1002, gid=1002, home=/home/user4
Oct 22 10:02:52 userseuac dovecot: imap(user4): Debug: Quota root: name=User 
quota backend=maildir args=
Oct 22 10:02:52 userseuac dovecot: imap(user4): Debug: Quota rule: root=User 
quota mailbox=* bytes=10485760 messages=0
Oct 22 10:02:52 userseuac dovecot: imap(user4): Debug: Quota rule: root=User 
quota mailbox=Trash bytes=+1048576 messages=0
Oct 22 10:02:52 userseuac dovecot: imap(user4): Debug: Quota warning: 
bytes=9961472 (95%) messages=0 reverse=no command=script 
/etc/dovecot/conf.d/teste 95 user4
Oct 22 10:02:52 userseuac dovecot: imap(user4): Debug: Quota warning: 
bytes=8388608 (80%) messages=0 reverse=no command=script 
/etc/dovecot/conf.d/teste 80 user4
Oct 22 10:02:52 userseuac dovecot: imap(user4): Debug: Quota warning: 
bytes=7340032 (70%) messages=0 reverse=no command=script 
/etc/dovecot/conf.d/teste 70 user4
Oct 22 10:02:52 userseuac dovecot: imap(user4): Debug: maildir++: 
root=/home/user4/Maildir, index=, control=, inbox=/home/user4/Maildir, alt=
 
# 2.0.14: /etc/dovecot/dovecot.conf
# OS: Linux 2.6.32-71.29.1.el6.x86_64 x86_64 CentOS Linux release 6.0 (Final)
auth_debug = yes
auth_debug_passwords = yes
auth_username_format = %Lu
auth_verbose = yes
disable_plaintext_auth = no
mail_debug = yes
mail_location = maildir:~/Maildir
mail_plugins = " quota"
mbox_write_locks = fcntl
passdb {
  driver = pam
}
plugin {
  mail_log_events = delete undelete expunge copy mailbox_delete mailbox_rename
  mail_log_fields = uid box msgid from subject size vsize flags
  quota = maildir:User quota
  quota_exceeded_message = Quota exceeded!!
  quota_rule = *:storage=10M
  quota_rule2 = Trash:storage=+1M
  quota_warning = storage=95%% script /etc/dovecot/conf.d/teste 95 %u
  quota_warning2 = storage=80%% script /etc/dovecot/conf.d/teste 80 %u
  quota_warning3 = storage=70%% script /etc/dovecot/conf.d/teste 70 %u
}
service quota-warning {
  executable = script /usr/local/bin/quota-warning.sh
  unix_listener quota-warning {
user = vmail
  }
  user = dovecot
}
ssl_cert = 

Re: [Dovecot] Getting the SMTP envelope through IMAP?

2011-10-22 Thread Hadmut Danisch
On 22.10.2011 10:15, Dennis Guhl wrote:
>> It's required for debugging purposes, writing mail filters, create
>> > blacklist filters from detected spam, etc.
> Disregarding end users mail filters this are all tasks for mailadmins
> which can tell thier MTA to write a reliable Return-Path: header and
> which have access to the corresponding maillog.

Definitely wrong.

Writing mail filters like ~/.mailfilter is a user's task. Training their
individual spam filters as well.

And whether you're even permitted to keep the maillog that long depends
on your local data protection laws.



And neither the Return-Path nor the  Received-Lines reveal the precise
date of delivery as the From line contains.


regards
Hadmut



Re: [Dovecot] Getting the SMTP envelope through IMAP?

2011-10-22 Thread Dennis Guhl
On Sat, Oct 22, 2011 at 12:00:34AM +0200, Hadmut Danisch wrote:
> On 21.10.2011 20:02, Dennis Guhl wrote:
> > The SMTP envelope does only exist within the involved MTAs and only as
> > long as the message is not finally delivered.
> 
> The intended use is to create a backup from a mailbox through IMAP,
> which is as close as possible to the original mbox file, thus resembling
> the FROM lines as well.

I don't think it will be possible. The tool for this would be rsync
(wich might be difficult if you only have IMAP access to the machine
in question).

> The envelope sender address does not drop it's meaning after delivery.

This I never claimed.

> It's required for debugging purposes, writing mail filters, create
> blacklist filters from detected spam, etc.

Disregarding end users mail filters this are all tasks for mailadmins
which can tell thier MTA to write a reliable Return-Path: header and
which have access to the corresponding maillog.

Dennis