放在页面代码上较顶部位置，偶试了可以的！

<SCRIPT language=JavaScript>

var currentpos,timer;
function initialize()
{
timer=setInterval ("scrollwindow()",30);
}
function sc()
{
clearInterval(timer);
}
function scrollwindow()
{
currentpos=document.body.scrollTop;
window.scroll(0,++currentpos);
if (currentpos!=document.body.scrollTop)
sc();
}
document.onmousedown=sc
document.ondblclick=initialize
</SCRIPT>