Mecanim state problem

Why doesn't this code toggle sprinting if the animator controller is in the sprint state:

 function Update () {
     var controller : CharacterController = GetComponent(CharacterController);
     if (controller.isGrounded) {
         var vert = Input.GetAxis("Vertical");
         var hori = Input.GetAxis("Horizontal");
         var sprinting = Input.GetButton("Sprint");
         if (hori != 0 || vert != 0) {
             anim.SetFloat(SpeedHash, 1);
         } else {
             anim.SetFloat(SpeedHash, 0);
         }
         anim.SetBool(SprintHash, sprinting);
         anim.SetFloat(DirectionHash, hori);
         
         moveDirection = new Vector3(hori, 0, vert);
         moveDirection = transform.TransformDirection(moveDirection);
         if (sprinting) {
             moveDirection *= sprintSpeed;
         } else {
             moveDirection *= speed;
         }
         if (Input.GetButton("Jump")) {
             moveDirection.y = jumpSpeed;
         }
     }
     moveDirection.y -= gravity * Time.deltaTime;
     controller.Move(moveDirection * Time.deltaTime);
 }

The walk state requires speed to be over 0.1 and will go back to idle if it's lower than that. It will go to Run if sprint is true and go back to Idle if it's false. But for some reason, the SetBool and SetFloat's doesn't work after the state has gone into Run. The mecanim parameters aren't even getting set after the state is Run, but the program is still receiving the right input.