我的javascript代码到底在哪出问题了？？？（新手求救）
<title>无标题文档</title><script language="javascript"id="clientEventHandlersJS">
function document_onmousemove()
{
form1.txtMousePosition.value=window.event.clientX+","+window.event.clientY;
}
</script>
<script language="javascript" for="document" event="onmousemove">
return document_onmousemove();
</script>
</head>
<body>
<form id="form1">
<p><input type="text" value="" name="txtMousePosition" size="20"/></p>
</form>
</body>
有的浏览器不兼用的！