ie6中pisition:fixed不起作用,浮窗不随屏滚动解决办法

.jumpbox{
position: absolute;
margin-left:-288px;
left:50%;
/*margin-top:-122px;*/
_margin-top:0px;
top:33%;
width:576px;
z-index:9999;
position:fixed!important;/*FF IE7*/
position:absolute;/*IE6*/
display:none;

_top: expression(eval(document.compatMode &&
document.compatMode==’CSS1Compat’) ?
documentElement.scrollTop + (document.documentElement.clientHeight-this.offsetHeight)/2 :/*IE6*/
document.body.scrollTop + (document.body.clientHeight – this.clientHeight)/2);/*IE5 IE5.5*/
}

background-image:url(about:blank);
background-attachment:fixed;

#bot-fixed{_position:absolute;_bottom:auto;_top:expression(eval(document.documentElement.scrollTop));}

#bot-fixed{_position:absolute;_bottom:auto;_top:expression(eval(document.documentElement.scrollTop+document.documentElement.clientHeight-this.offsetHeight-(parseInt(this.currentStyle.marginTop,10)||0)-(parseInt(this.currentStyle.marginBottom,10)||0)));}

g1 = (getClientHeight() – o.height) / 2;//1000px总 元素高300px 则 g1=350px
g2 = g1 / getClientHeight();//350/1000 = 0.35
g2 = Math.round(g2 * 100) – 1;//=34 四去五入 大于五全部加，等于五正数加，小于五全不加。
$(‘.jumpbox’).css(‘top’, g2 + ‘%’);
$(‘.jumpbox’).css(‘height’,document.body.scrollHeight);
if ($.browser.msie && $.browser.version == “6.0″) {
default_top1=document.documentElement.scrollTop+150+”px”;
$(‘.jumpbox’).css(“top”,default_top1);
$(window).scroll(function() {
default_top2=document.documentElement.scrollTop+150+”px”;
$(‘.jumpbox’).css(“top”,default_top2);

})

}