dovecot - Feb 2012 - duplicates with multiple To/CC and sieve redirect copy

Hi,
In one installation we are using sieve "redirect :copy" to create copy
of the incoming email (local boss gets copy of its employees mails).
There is a problem when the incoming email has multiple To/CC entries 
with local users. Multiple copy/redirects are created (one for each 
employee) and there are multiple copies in "boss" account.
Each of this emails has the same Message-ID.

Is there a way to detect those duplicates and discard them when saving 
copies into boss account?

There was a discussion on the list a while ago (Feb 10/11, 2011) 
mentioning this problem, but with no clear solution.

We are using Dovecot 2.0.15. Mail is delivered via LMTP (MDA/postfix is 
on separate machine then MAA/dovecot).

-- 
Adam Szpakowski

On 22.2.2012, at 0.46, Adam Szpakowski wrote:
> In one installation we are using sieve "redirect :copy" to create
copy of the incoming email (local boss gets copy of its employees mails).
> There is a problem when the incoming email has multiple To/CC entries with
local users. Multiple copy/redirects are created (one for each employee) and
there are multiple copies in "boss" account.
Could this instead be implemented by MTA as automatic bcc: boss of all incoming
mails?

On 21.02.2012 23:57, Timo Sirainen wrote:
> On 22.2.2012, at 0.46, Adam Szpakowski wrote:
>> In one installation we are using sieve "redirect :copy" to
create copy of the incoming email (local boss gets copy of its employees mails).
>> There is a problem when the incoming email has multiple To/CC entries
with local users. Multiple copy/redirects are created (one for each employee)
and there are multiple copies in "boss" account.
> Could this instead be implemented by MTA as automatic bcc: boss of all
incoming mails?
Unfortunately no. The employee/boss structure is quite complicated. Some 
employees have multiple "bosses", there are also some
"project" emails
when the structure is even more complicated.
We are using dedicated sieve_before script for each user based on %u 
variable.
-- 
Adam Szpakowski