public function createListElement( core_kernel_classes_Class $listClass, $label = '')
    {
        $returnValue = null;

        
        
        if(!is_null($listClass)){
			$level = count($this->getListElements($listClass)) + 1;
        	if(empty($label)) {
	        	$label = __('Element') . ' ' . $level;
	        }
	        $returnValue = $this->createInstance($listClass, $label);
	        $this->bindProperties($returnValue, array(TaoOntology::PROPERTY_LIST_LEVEL => count($this->getListElements($listClass, false))));
        }
        

        return $returnValue;
    }