protected function processOutputAttribute(Mage_Core_Model_Layout_Element $node)
    {
        if (isset($node['output'])) {
            $blockName = (string)$node['name'];
            if (empty($blockName)) {
                return;
            }
            $method = trim((string)$node['output']);
            if (empty($method)) {
                $this->removeOutputBlock($blockName);
            } else {
                $this->addOutputBlock($blockName, $method);
            }
        }
    }