Script error notification is not sent to Exec method of WebBrowser Host

#define CHECK_HR(hr,label) \ 
if(FAILED(hr)) \ 
{	goto label; \ 
}

#define RRELEASE(ptr) \ 
if(ptr) \ 
{	ptr->Release(); \ 
	ptr = NULL; \ 
}

// Get the DOM associated with the WebBrowser that threw this event, and
// inject an onerror tag into the page in hopes of receiving an 
// OLECMDID_SHOWSCRIPTERROR message. (This is a bug in Internet Explorer 6.)
// NOTE: pBrowser is the IWebBrowser2 for the FRAME, IFRAME, or primary 
// that just finished loading our document. If you have a FRAMESET with 
// three FRAMEs, you will see this handler called four times: once for 
// each FRAME and once for the FRAMESET after all FRAMEs have loaded. 
// We're sinking each individual FRAME in this sample; to sink only the 
// topmost FRAME, test the IUnknown of our m_pBrowser against the IUnknown 
// of this method's pBrowser, and sink only when these two are equal. 
void CSimpleBrowserDlg::OnDocumentComplete(LPDISPATCH pBrowser, LPVARIANT url) 
{
	IWebBrowser2 *thisBrowser		= NULL;
	IDispatch *docDisp			= NULL;
	IHTMLDocument3 *doc		= NULL;
	IHTMLElement *elem			= NULL;
	HRESULT hr = S_OK;

	hr = pBrowser->QueryInterface(IID_IWebBrowser2, reinterpret_cast<void **>(&thisBrowser));
	CHECK_HR(hr, cleanup);
	hr = thisBrowser->get_Document(&docDisp);
	CHECK_HR(hr, cleanup);
	hr = docDisp->QueryInterface(IID_IHTMLDocument3, reinterpret_cast<void**>(&doc));
	CHECK_HR(hr, cleanup);
	RRELEASE(docDisp);

	// Get the documentElement for the document object, and then call 
	// IHTMLElement::insertAdjacentHTML() to add the onerror SCRIPT 
	// handler tag.
	hr = doc->get_documentElement(&elem);
	CHECK_HR(hr, cleanup);
	// NOTE: The &nbsp, or some other visible HTML, is required. Internet Explorer will not
	// parse and recognize the script block without some visual HTML to
	// accompany it.
	hr = elem->insertAdjacentHTML(L"afterBegin", L"&#xa0;<SCRIPT For='window' Event='onerror'>var noOp = null;</SCRIPT>");

	// Cleanup.
cleanup:
	RRELEASE(elem);
	RRELEASE(thisBrowser);
	RRELEASE(doc);
}