//240purge_trash_keep
// when purging Trash folder, purge messages older than how many days?
$_prefs['purge_trash_keep'] = array(
    'value' => 30,
    'locked' => false,
    'shared' => false,
    'type' => 'number',
    'desc' => _("Purge messages in Trash folder older than this amount of days."),
    'help' => 'prefs-purge_trash_keep');

