Why does GetPxRigidBody function return normally pointer for movable staticmeshactor only?

Hi~ Guys

I am setting USECCD flag at StaticMeshActor into Current Level.

When StaticMeshActor that mobility property is static returned NULL pointer for GetPxRigidBody() function,

I changed mobility property from static to movable, then GetPxRigidBody() function returned normally pointer.

Is this normall or bug?

How can i get pointer of PxRigidBody for static mobility actors?