Problem with sieve configuration on dovecot+debian_jessie+ISPC3

[Filip Loncar [WarpMax | FederationServers]]

I'm new-ish to dovecot and sieve (haven't used it extensively till now) 
and I'm not sure that I configured everything propperly.

The problem is that we're trying to get the following sieve code to run:

require ["fileinto", "regex", "date", "relational", "vacation", 
"duplicate"];



require "duplicate";
    if duplicate :header "message-id" {
      discard;
    }
     else
   {
redirect "<somemail1>";
redirect "<somemail2>";
redirect "<somemail3>";
redirect "<somemail4>";
redirect "<somemail5>";
redirect "<somemail6>";
keep;
}

keep;


But we're constantly getting the following error:

sieve: info: started log at Aug 02 08:13:21.
main script: line 5: error: require command: unknown Sieve capability 
`duplicate'.
main script: line 6: error: unknown test 'duplicate' (only reported once 
at first occurence).
main script: error: validation failed.

Both me and my collegue can't find what's wrong with the system.

I would appreciate any kind of help on this matter.

Below's my configuration.

# dovecot --version
2.2.13

# dovecot -n
# 2.2.13: /etc/dovecot/dovecot.conf
# OS: Linux 2.6.32-45-pve x86_64 Debian 8.5
auth_mechanisms = plain login
disable_plaintext_auth = no
listen = *,[::]
log_timestamp = "%Y-%m-%d %H:%M:%S "
mail_privileged_group = vmail
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 vnd.dovecot.duplicate
passdb {
   args = /etc/dovecot/dovecot-sql.conf
   driver = sql
}
plugin {
   quota = dict:user::file:/var/vmail/%d/%n/.quotausage
   sieve = /var/vmail/%d/%n/.sieve
   sieve_duplicate_default_period = 14d
   sieve_extensions = +vnd.dovecot.duplicate
   sieve_max_redirects = 6
   sieve_plugins = sieve_extprograms
}
protocols = imap pop3
service auth {
   unix_listener /var/spool/postfix/private/auth {
     group = postfix
     mode = 0660
     user = postfix
   }
   unix_listener auth-userdb {
     group = vmail
     mode = 0600
     user = vmail
   }
   user = root
}
service imap-login {
   client_limit = 1000
   process_limit = 500
}
ssl_cert = </etc/postfix/smtpd.cert
ssl_key = </etc/postfix/smtpd.key
ssl_protocols = !SSLv2 !SSLv3
userdb {
   args = /etc/dovecot/dovecot-sql.conf
   driver = sql
}
protocol imap {
   mail_plugins = quota imap_quota
}
protocol pop3 {
   mail_plugins = quota
   pop3_uidl_format = %08Xu%08Xv
}
protocol lda {
   mail_plugins = sieve quota
}

# uname -a
Linux fero 2.6.32-45-pve #1 SMP Wed Mar 30 12:22:08 CEST 2016 x86_64 
GNU/Linux

It's a Debain Jessie VM running ISPC3.

-- 
Srdac(an pozdrav | Best regards
Filip Lonc(ar
___________________________________________

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