The Walking Dead Game Animation Style

Hi, I am trying to accomplish so that at a certain point in the game, I can press a key (W) and it will play the animation onwards until I stop holding the key. This effect has been seen in The Walking Dead Game made by Telltale games, released april 24th 2012. Here's an example of what I mean : Link to example video

Yesterday, april 26th 2013, I found a way to accomplish this with a javascript. But I also discovered a problem when I have release the key and pressing it again, the animation buffers some frames forward in time, and I don't want that. Here is my script :

 var TestObject : GameObject;
 
 function Update () {
 
  if(Input.GetKey("w")){
  TestObject.animation.Play();
  
  
  TestObject.animation.enabled = true;
  
  
  
  }
 
 else
 
 if(!Input.GetKey("w")){
 
 TestObject.animation.enabled = false;
 
 
 
 
 
 }
 
 
 
 }

How can I make the animation resume smoothly from the last frame instead of just buffering a couple of frames forward?