VB里怎样调用VC的COM接口中[out]类的参数,该如何解决

[id(1), helpstring("method TestMethod")] HRESULT TestMethod([out] BSTR* outstr, [out] double* outdbl, [out] IDispatch** outobj);

STDMETHODIMP CTestClass::TestMethod(BSTR *outstr, double *outdbl, IDispatch **outobj)
{
    *outstr = _bstr_t("你好!").copy();
    *outdbl = 3.1415926;
    _COM_SMARTPTR_TYPEDEF(IDispatch, __uuidof(IDispatch));
    IDispatchPtr p;
    p.CreateInstance("scripting.dictionary");
    *outobj = p;
    p.AddRef();
    return S_OK;
}