3D-rotated MovieClip - Smoothing

Hello there!
I have 2x MovieClips that contains tiles.
The lower MovieClip is the floor and the other is a wall.

As you can see, the floor isn’t that smooth as I would it to be.
I have tried many things, but none of them seems to work.
Here are a few things I’ve tried:
[LIST]
[]Bitmap.smoothing = true;
[
]myBitmapData.draw(… smoothing = true);
[*]mySprite.graphics.beginBitmapFill(… smoothing = true);
[/LIST]If you know any other way to hopefully smooth it,
please let me know so I can try :thumb2:

Thanks in advance!
~Tompa