GuiBitmapCtrl setBitmap Issues

I'm having issues with adding a GBitmap to a canvas. I've created a simple example (below) to demonstrate my problem - when using a path, setBitmap works with no problems but when I try to use the GFXTexHandle, it shows the outline of the boundary box but nothing else.

GBitmap * gbitmap = new GBitmap(100, 100);
gbitmap->fill(ColorI::BLUE);
GFXTexHandle * gth = new GFXTexHandle(gbitmap, &GFXDefaultGUIProfile, false, "someText");

GuiBitmapCtrl * gbc = new GuiBitmapCtrl();
gbc->registerObject();

// This doesn't work
gbc->setBitmap(*gth);
// This works fine	
//gbc->setBitmap("face.png");

gCanvas->getContentControl()->addObject(gbc);