MeshCollider (concave) doesn't trigger OnCollision functions

Hello guys,

I searched at Google and I'm very suprised that nobody mentioned about MeshCollider (concave) doesn't support for method "OnCollision". So I'll ask here:

I've there a problem with MeshCollider. The problem is that MeshCollider (concave) will not trigger on OnCollisionEnter (but convex/other collider works fine). It looks like that MeshCollider in concave doesn't support in OnCollisionEnter or I'm wrong?

If I'm wrong, how I can find out if the point is inside of mesh (concave + convex)? The calculation should be fast (good for performance, optimized). I'm using very few poly (low poly) for mesh.

I can't use convex because I need to find out if a point is inside of mesh, in convex and even in concave. I can't also use trigger from meshcollider, because the trigger works only in convex. I can't use multiple convex mesh (or submesh) to make it "fake"-concave mesh (like this: https://www.assetstore.unity3d.com/en/#!/content/4596), because I need raycast "triangleIndex" which it doesn't work in convex.

Does anybody have a idea?

Thanks!