[ingo] Help wanted with backend configuration

[VALOIS, Pascal]

I configured the following backend.local.php in ingo to add filter 
support with sieve.
But when i modify filters, i see imap2 connexion to the server and no 
connection to timsieve (port 2000).

Is there anything wrong with this backend ?

And another question. In previous releases of horde/imp/ingo we could 
use "'preferred' => ($_SESSION['imp']['server']),".
but when i use $_SESSION['imp']['server'] in hostspec, it tells me that 
there is no such variable.
is there a way to do this in this new release ?

My backend :

<?php
$backends['sieve'] = array(
     // Disabled by default
     'disabled' => false,
     'transport' => 'timsieved',
     'hordeauth' => 'full',
     'params' => array(
         // Hostname of the timsieved server
         //'hostspec' => ($_SESSION['imp']['server']),
         'hostspec' => 'helios',
         // Login type of the server
         'logintype' => 'PLAIN',
         // Enable/disable TLS encryption
         'usetls' => true,
         // Port number of the timsieved server
         'port' => 2000,
         // Name of the sieve script
         'scriptname' => 'ingo',
         // The following settings can be used to specify an administration
         // user to update all users' scripts. If you want to use an admin
         // user, you also need to disable 'hordeauth' above. You have 
to use
         // an admin user if you want to use shared rules.
         // 'username' => 'cyrus',
         // 'password' => '*****',
         // Enable debugging. With Net_Sieve 1.2.0 or later, the sieve 
protocol
         // communication is logged with the DEBUG level. Earlier versions
         // print the log to the screen.
         'debug' => true,
     ),
     'script' => 'sieve',
     'scriptparams' => array(
         // If using Dovecot or any other Sieve implementation that requires
         // folder names to be UTF-8 encoded, set this parameter to true.
         'utf8' => false,
      ),
     'shares' => false
);

?>

-- 
Pascal Valois
Service Informatique
Pôle Universitaire Leonard de Vinci