why Preloading not include external flv

hello

i use a preloader in frame 1 for my project , when i put some image or graphic on Frame 2 the preloader works well and spend a time to load all of them ..

but now i want i put an extrenal FLV videos to Frame 2 and when i do this the preloader not show for a while and then run fast , it seems the preloader not calculate my Flv at all !!

this is my Main script of preloader :

function update(e:Event)
{
    var percentage:int;    
    
    percentage = Math.round(stage.loaderInfo.bytesLoaded*100/stage.loaderInfo.bytesTotal);    
    display.text = String(percentage) + "%";
    
    if(percentage >=100)
    {
        display.text = "100%";
        
        updateTimer.removeEventListener(TimerEvent.TIMER, update);
        updateTimer.stop();
        updateTimer = null;        
        
        // play or stop on the next frame for the loade parent
        if(!onFinishPlayParent)
            parentMc.gotoAndStop(parentMc.currentFrame+1);
        else    
            parentMc.gotoAndPlay(parentMc.currentFrame+1);                
            
        new EazeTween(this).to(1,{alpha:0});    
    }

}

so how can i set preloader to calculate my external data for loading too ?  

cause i dont want to import my FLv to timelinewith 1600 frames !!!

thanks ...