[away3d] Front and back faces swapped on Cube

[ConteZero]

I've tested Away3d 2.3 and I've seen that front and back faces are
swapped on Cube primitive.
If I use:

cube = new Cube( {width:200, height:200, depth:200, faces:
{front:material1, back:material2, top:material, bottom:material,
right:material, left:material} } );

The result is:

Away3d 2.2
front face uses material1
back face uses material2

Away3d 2.3
front face uses material2
back face uses material1