Missing FLVPlayback and VideoEvent

I’m trying to import and use the classes, FLYPlayback and VideoEvent, I use the following code to import them,

import fl.video.FLVPlayback;
import fl.video.VideoEvent;

When I publish, I get the error code,

1046: Type was not found or was not a compile-time constant: FLVPlayback.
public var video:FLVPlayback;

1180: Call to a possibly undefined method FLVPlayback.
video = new FLVPlayback();

1172: Definition fl.video:VideoEvent could not be found.
import fl.video.VideoEvent;

1172: Definition fl.video:VideoEvent could not be found.
import fl.video.FLVPlayback;

What could I be doing wrong, from what it looks like, my version of flash (registered CS3) can’t find these classes.

Any help or advice would be great thanks.