ninja gaiden II Easter Egg - Hidden Xbox Prototype

In chapter 4, there is a scene when you reach the statue of liberty, on the bottom floor of it there is a small museum full of old Japanese artifacts. Now, near the door on the other side of the place from where you came in. in the display case you can see a part of it is blocked off with some sort of wood. attack it and it will break away. and you will see the shiny xbox prototype sitting inside it. also if you press r2 on it, you will hear the xbox 360 start up noise.