If you use the Collision class and therein the Collision.contacts (which is an array of contactpoints) you should be able to...
function OnCollisionStay(collision : Collision) {
for (var contact : ContactPoint in collision.contacts) {
print(contact.thisCollider.name + " hit " + contact.otherCollider.name);
// Visualize the contact point
Debug.DrawRay(contact.point, contact.normal, Color.white);
}
}
Try getting the size of the contacts array and look at the last points.
// Print how many points are colliding this transform
// And print the first point that is colliding.
function OnCollisionEnter(other : Collision) {
print("Points colliding: " + other.contacts.Length);
print("First point that collided: " + other.contacts[0].point);
}