QGLWidget overlay context

Hi,
I am setting up a QGLWidget to perform some rendering. I would like to enable the overlay context but it doesnt seem to be working on my windows 7 64-bit machine.

Here is the code :

Code:

---

// allocate the hidden viewport
	hiddenViewPort = new QGLWidget(QGLFormat(QGL::HasOverlay|QGL::DoubleBuffer|QGL::DepthBuffer|QGL::Rgba|QGL::AlphaChannel|
	                                         QGL::AccumBuffer|QGL::StencilBuffer|QGL::NoStereoBuffers|QGL::DirectRendering));
 
	// get the format
	QGLFormat format = hiddenViewPort->format();
 
	// test it's capabilities
	if(!format.hasOverlay())
		vcl_cerr << "qViewManager : no overlays\n";
 
	if(!format.doubleBuffer())
		vcl_cerr << "qViewManager : got single buffer\n";
 
	if(!format.depth())
		vcl_cerr << "qViewManager : no depth buffer\n";
 
	if(!format.rgba())
		vcl_cerr << "qViewManager : index color\n";
 
	if(!format.directRendering())
		vcl_cerr << "qViewManager : no direct rendering\n";

---

The hasOverlay() check on the format is always false. Is this behaviour to be expected on my platform?

If so what are my other options for drawing GL_POINTS etc... in my QGLWidget?

Thanks,
Dave...