Blackspot removal in Mental Ray : 3ds max 9

I’ve made a small example of a light fitting luminaire where the Black spots appear during render and they can be removed by using a mental ray shader available from David Lanier : Download Black Spot Removal Shader

Black Spots can be seen in this render
black spots in mental ray

Black Spots removed using DL3D shader
black spots removed with dl3d shader

Final image rendered with Mental Ray 3ds max 9
final luminaire render with mental ray