[imp] unable to solve double sent-mail and Trash folder

[jkpsj]

I have been trying to solve this issue on my own for the past 2 weeks but my effort was in vain.
The thing that puzzled me is that the double appearances of sent-mail and Trash is NOT consistent
throught users.

Some 80% of the users are OK. While the rest have their sent mail folders as .sent-mail and
.INBOX.sent-mail while trash folders as .Trash and .INBOX.Trash

I think I have setup prefs.conf correctly as:
$_prefs['sent_mail_folder'] = array(
    'value' => 'sent-mail',
    'locked' => false,
    'shared' => true,
    'type' => 'implicit'
);

$_prefs['use_trash'] = array(
    'value' => 1,
    'locked' => true,
    'shared' => false,
    'type' => 'checkbox',
    'desc' => _("When deleting messages, move them to your Trash folder instead of marking them as
deleted?")
);

$_prefs['trashselect'] = array('type' => 'special');

//my courier-imap trash folder name is Trash
//and I have also set IMAP_MOVE_EXPUNGE_TO_TRASH=0
$_prefs['trash_folder'] = array(
    'value' => 'Trash',
    'locked' => true,
    'shared' => false,
    'type' => 'implicit'

and in servers.php, I have this:
$servers['imap'] = array(
    'name' => 'my imap svr',
    'server' => 'imap.example.com',
    'protocol' => 'imap/notls',
    'port' => 143,
    'folders' => 'INBOX.',
    'namespace' => '',
    'maildomain' => 'example.com',
    'smtphost' => '',
    'realm' => '',
    'preferred' => ''
);


I would greatly appreciate any single piece of information that I could use to solve this.
My setup:
IMAP-2001.FINAL
Courier imap 1.7.0
horde 2.2.1
imp 3.2
php-4.3.2

best rgds.


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