CogetInterceptor

I use CoGetInterceptor API to intercept function calls from an
interface in a BHO plugin. IWebBrowser2 interface is intercepted in
SetSite.
It intercepts the calls in INVOKE of the BHO (IWebBrowser2 -------


IWebBrowser2 ---->getdocument in other BHO plugins unless it is
intercepted inside that BHO. Deubugging shows that it is having same
memory address referred.

//define function pointer for CoGetInterceptor API in OLE32.DLL
typedef HRESULT (__stdcall * getInterceptor)(
           REFIID ,
                       IUnknown* ,
                       REFIID ,
                       void** );

getInterceptor fptrgetInterceptor;
HINSTANCE hinstLib;

class CCallFrameEvents : public ICallFrameEvents
{
public:
public:
// CCallFrameEvents

// ICallFrameEvents
    //intercepted object function calls come
    //to the OnCall handler
    STDMETHOD(OnCall)(ICallFrame* pCallFrame)
    {
                               //all the object function calls comes
                                //here after interception
        MessageBox(NULL,
                                _T("CCallFrameEvents::OnCall intercept
handler"), _T("ICallFrameEvents"),0);
        return S_OK;
    }

// IUnknown
    STDMETHOD_(ULONG, AddRef)()
    {
        return 1;
    }
    STDMETHOD_(ULONG, Release)()
    {
        return 1;
    }
    STDMETHOD(QueryInterface)(REFIID InterfaceIdentifier, VOID**
ppvObject)
    {
        return E_NOINTERFACE;
    }
};

ICallInterceptor* pCallInterceptor;
CCallFrameEvents pHandler ;

//IN SET SITE OF BHO
STDMETHODIMP CIHTMLFormAnalyse::SetSite(IUnknown *pUnkSite)
{
         CComQIPtr<IWebBrowser2, &IID_IWebBrowser2> m_pQIWebBrowser2;
         m_pQIWebBrowser2 = pUnkSite;
         fptrgetInterceptor = NULL;
         // Get a handle to the DLL module.
         hinstLib = LoadLibrary(_T("ole32.dll"));
         if(hinstLib != NULL)
         {
               //get the address of the CoGetInterceptor function
               fptrgetInterceptor = (getInterceptor)GetProcAddress
(hinstLib, "CoGetInterceptor");
         }

      if(fptrgetInterceptor != NULL)
      {
    hr = fptrgetInterceptor(__uuidof(IWebBrowser2), NULL,
__uuidof(ICallInterceptor),(VOID**)&pCallInterceptor);
    if(pCallInterceptor != NULL)
    {
                          //register sink with callback class
                           hr = pCallInterceptor-


                           //query the interface of object whose
                           //function calls should be intercepted
                            hr = pCallInterceptor->QueryInterface
(&m_pQIWebBrowser2.p);
               }
     }
}

Thanks in advance