Front polygons lit from the back on a static mesh

This might be a bit weird to explain. Basically, I made a plane on 3DS max, then that mesh acts as an inside wall in a building. So, it should block light, cast a shadow and it will be inside the shadow.

I set the lightmass settings for Use Two Sided Lighting and Shadow Two Sided to true. So, the plane mesh does cast a shadow, but it is lit up as if it was facing the light.

Sky light comes from left to right, back to front. The wall with the bricks and windows on the left is casting the shadow to the floor and the wall on the right. However, you can see that it’s oddly lit, it should be in a shadow. The wall on the right receives the shadows and is properly lit, as if it’s inside of a building.

http://puu.sh/t3TuZ/aaf00ad1e3.jpg

This is the view from the back.

https://puu.sh/t3TA9/862f9ee49e.jpg

This is the walls that are on the direction of the sky light. Notice the beams being in a shadow, but the walls are lit.

http://puu.sh/t3TEA/1cac4ba5b9.jpg

This is the opposite side from where the light is coming from, what I want to see, but with the light coming through the windows.

http://puu.sh/t3THn/4ed69d875c.jpg

This is the second set of static meshes that I build, I didn’t have this problem before. The mobility for all lights and the wall meshes are set to Static.