Problem with fxlight and item light

Have a quick question about fxLight. I placed a few lights around a level inside a DIF building. However, the light can be seen on the other side of the wall as well. This happens also with any item that emits light, like the crossbow bolt.

I checked both 3DGPAI1 and A3DGPAI1 books and browsed the forums but there is no mention on any settings to prevent this other than having to get the TLK.

Any help would be greatly appreciated.