I have noticed a tiny bug in skybox. The far corner gets clipped by far frustrum plane, no matter what is the distance to my far frustrum. I browsed the sources and found that the skybox overrides the function “pushModelViewProjection” and contains the code
var size : Number = camera.lens.far / Math.sqrt(3);
looks like this “far / Math.sqrt(3)” makes the box a bit bigger than required!
See the screenshot of the corner.