a PROGRESS event when uploading ByteArray to server with AS3 & PHP

I'm currently creating a series of as3 / PHP classes that upload - encode + download images.

Anyone know if there's a way to report progress while posting a ByteArray to the server?

the ProgressEvent is not working - at least not in the case of uploading a ByteArray -
it reports progress only after it's been uploaded

here's a stripped version of the code I'm using ...

urlLoader=new URLLoader;
urlLoader.dataFormat=URLLoaderDataFormat.BINARY;
urlLoader.addEventListener(ProgressEvent.PROGRESS,progressHandler);
//          
function progressHandler(e:ProgressEvent):void {
              trace(e.bytesLoaded/e.bytesTotal);

}

thanks -MW