public function getTree($renderer = 'Horde_Core_Tree_Renderer_Html')
{
$tree = $GLOBALS['injector']->getInstance('Horde_Core_Factory_Tree')->create('mime-' . $this->getUid(), $renderer, array('nosession' => true));
foreach ($this->_message->partIterator() as $val) {
$this->_addTreeNodes($tree, $val);
}
return $tree;
}