[horde] Problems with IMAP-Folder

[info@web-front.de]

Hello,

my system: Horde 3.0.9, IMP 4.0.4, Turba2 on Debian sarge

My Problem:

I can't see the IMAP-Folder, which my users created with Email-Clients(Thunderbird, Outlook)

/imp/config/prefs.php
entry in
Line 243:
// use IMAP subscribe?
// value of 0 = no, 1 = yes
$_prefs['subscribe'] = array(
    'value' => 1,
    'locked' => false,
    'shared' => false,
    'type' => 'checkbox',
    'desc' => _("Use IMAP folder subscriptions?"));

entry in
/imp/config/servers.php
$servers['imap'] = array(
    'name' => 'IMAP Server',
    'server' => 'mail.my-domain.de',
    'hordeauth' => false,
    'protocol' => 'imap/notls',
    'port' => 143,
    'folders' => 'mail/',
    'namespace' => '',
    'maildomain' => 'my-domain.de',
    'smtphost' => 'mail.my-domain.de',
    'smtpport' => 25,
    'realm' => 'my-domain.de',
    'preferred' => '',
    'dotfiles' => false,
    'hierarchies' => array()
);


Please help me.

Kind Regards
Thomas