public function schemaValidate(DOMDocument $doc, $xsdName)
    {
        $errors = array();
        set_error_handler(function ($errno, $errstr) use (&$errors) {
            $errors[] = "'$errstr' [Errno $errno]";
        });
        $cfg = Mage::helper('radial_core')->getConfigModel();
        $isValid = $doc->schemaValidate(Mage::getBaseDir() . DS . $cfg->apiXsdPath . DS . $xsdName);
        restore_error_handler();
        if (!$isValid) {
            $msg = sprintf(
                "[ %s ] Schema validation failed, encountering the following errors:\n%s",
                __CLASS__,
                implode("\n", $errors)
            );
            throw new Radial_Core_Exception_InvalidXml($msg);
        }
        return $this;
    }