DOMXPathResult *xpathResult = static_cast<DOMXPathResult*> (
        static_cast<DOMXPathEvaluator*>(pXmlDoc)->evaluate(
            XMLString::transcode("/HUJ/PIZDACFG/PizdaCfg/@FooBarEnabled"),
            pXmlDoc, NULL, DOMXPathResult::NUMBER_TYPE, NULL
            )
        );

    double attrVal = xpathResult->getNumberValue();
    int bAttrVal = static_cast<int>(attrVal);
    m_fooBarEnabled = (bAttrVal == 1);
    return 0;

не пишите на плюсах пацаны