FLVPlayback component

Please advice on the following inquiry:
I use FLVPlayback component and I want to create a button which will rewind a frame back. Encoding the flv sets the keyframes. Is there a way to take all the keyframes (in order to set the logic for the button), or should I the last one I have gone trough? I need the keyframes because “seek()” sends to keyframe. The logig for the one-frame-forward button is:
var listenerObject:Object = new Object();
var lastTime:Number=0;
listenerObject.playheadUpdate = function(eventObject:Object):Void {
trace("playhead time is: " + eventObject.playheadTime);
lastTime=eventObject.playheadTime;
};
my_FLVPlybk.addEventListener(“playheadUpdate”, listenerObject);
my_FLVPlybk.seek(lastTime+(1/my_FLVPlybk.metadata.framerate));