c'era qualche errore nel codice, così funziona

Codice PHP:
_global.loadMedia = function(myFile:StringmyMC:MovieClip) {
    var 
mediaListner:Object = new Object();

    
mediaListner.onLoadInit myLoadInit;
    
mediaListner.onLoadStart myLoadStart;
    
mediaListner.onLoadProgress myLoadProgress;
    
mediaListner.onLoadComplete myLoadComplete;
    
mediaListner.onLoadError myLoadError;

    function 
myLoadInit(target_mc:MovieClip) {
        
trace("Initialized "+target_mc);
    }

    function 
myLoadProgress(target_mc:MovieCliploadedBytes:NumbertotalBytes:Number) {
        
trace("Percentuale Caricamento: "+Math.floor((loadedBytes/totalBytes)*100)+"%");
    }

    function 
myLoadComplete(target_mc:MovieClip) {
        
trace("<< Procedura terminata >>");
    }

    function 
myLoadError(target_mc:MovieCliperrorCode:StringhttpStatus:Number) {
        
trace("Si è verificato un ERRORE durante il caricamento del file: "+myFile+" "+target_mc);
        
trace(">> ====================================");
        
trace(">> error downloading image into "+target_mc);
        
trace(">>errorCode: "+errorCode);
        
trace(">>httpStatus: "+httpStatus);

    }

    function 
myLoadStart(target_mc:MovieClip) {
        
trace("<< Avvio della procedura di caricamento >>");
    }

    var 
mcLoader:MovieClipLoader = new MovieClipLoader();
    
mcLoader.addListener(mediaListner);
    
mcLoader.loadClip(myFilemyMC);
};