如果用JavaScrpt动态指定Flash的路径？

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<META NAME="Generator" CONTENT="EditPlus">
<META NAME="Author" CONTENT="">
<META NAME="Keywords" CONTENT="">
<META NAME="Description" CONTENT="">
</HEAD><BODY>
<span id="flash"></span>
<SCRIPT LANGUAGE="JavaScript">
<!--
var url = "flash/movie.swf";
flash.innerHTML="这里是flash:"+"<embed src=\""+url+"\" quality=\"high\" width=\"438\" height=\"320\"></embed>";//-->
</SCRIPT>
</BODY></HTML>