Weird 3D Ball movement after Unity 5 Upgrade

Hi, i recently got a weird problem after upgrading my project to Unity 5.

so, a normal ball with rigidbody attached, are not moving at first load, that’s normal.
but when i add some impulse forces to the ball it never stop (even i set the Drag to 1). then i break it’s movement by executing this script:

 GetComponent<Rigidbody>().velocity = Vector3.Lerp (GetComponent<Rigidbody>().velocity,, 0.1f)

it slows down and stop correctly, but when I lift up my finger. the ball are moving again (but in low speed) and I didn’t give the ball any command to move them again.

what happens??? it is because of PhysX upgrade maybe???

ok, this question is now SOLVED.

it’s because of limitation on Mesh Collider on PhysX 3.3. so :

GetComponent<Rigidbody>().isKinematic = false;
GetComponent<Rigidbody>().velocity = Vector3.Lerp (GetComponent<Rigidbody>().velocity,, 0.1f)
if(GetComponent<Rigidbody>().velocity < 0.1f)
GetComponent<Rigidbody>().isKinematic = true;

note : this bug is ONLY appear when hit with Mesh Collider.