OK, I've found an easy test that anyone should be able to confirm (or not). Open the standard material test scene, and apply a 242 white lambert material to the entire ball (grey pieces too), and the ground plane. Red dots all along the gap between the inner ball and outer ball, with some more scattered throughout the rest of the shadow areas.
EDIT: I tried decreasing the brightness of the material in steps of 5. I am getting red dots all the way down to RGB227, no dots at RGB222.