protected function _getSelectedNodes()
 {
     if (version_compare(Mage::getVersion(), '1.4.0.0', '>=')) {
         return parent::_getSelectedNodes();
     }
     if ($this->_selectedNodes === null) {
         $this->_selectedNodes = array();
         $root = $this->getRoot();
         foreach ($this->getCategoryIds() as $categoryId) {
             if ($root) {
                 $this->_selectedNodes[] = $this->getRoot()->getTree()->getNodeById($categoryId);
             }
         }
     }
     return $this->_selectedNodes;
 }