Help With Scale Effect

Hello all I had a quick question as to how to go about doing this type of scale effect ( I think!!) here is the link http://www.kia-rio.com/main.htm.

I am trying to do the effect after the preloader is loaded how the square zooms to and opened fixed width and I believe a movie clip is loaded inside at what I think is a fixed width also.

Is it a drawn square that is being scaled? or is it a movie clip being scaled?

If someone could help me with and .fla example so I can understand that would be great or any help in general thanx :slight_smile: