Video class getting confused about which dimensions to use

I’m having a very bizarre problem with the Video class. I had this issue in a large project but managed to reproduce the problem in four lines of code

var videoA:Video = new Video( 123, 123 );
trace( [ videoA.width, videoA.height ] );
var videoB:Video = new Video( 456, 456 );
trace( [ videoB.width, videoB.height ] );

Create a new AS3 FLA, type that code into frame 1 and run it. You would expect to get the following:

123 123
456 456

But this is what I have got on three separate installations of Flash CS3:

123 123
123 123

I experienced this problem in a project that needed to play two videos, back to back. the second video had different dimensions to the first. The first one behaves as expected. But the second one seems to take on the dimensions of the first. Then if I remove all references to the first one, the second one starts behaving.

I can work around the issue by setting the dimension of the video after constructing it, but then I’m only setting the DisplayObject width and height, which means I’m messing with the scale. And that causes more problems.

Can anyone shed some light on this?