Importing Smooth Bind From Maya - Unity

Hello,

I have an animation of an arm in Maya which is using smooth bind joints. When I import this into Unity, the arm does not animate. The joints have the animation, but the mesh of the arm isn't following it - Why is this?

Can someone help me please??

Thanks

Got it working - turns out I was doing something wrong within Maya -- I needed to place my joints into the arm as a child