经典的问题,用滤镜
http://blog.csdn.net/nb_pdd/article/details/5880643
可以导入http://www.dillerdesign.com/experiment/DD_belatedPNG/这个类库,用ie条件注释判断是ie6导入这个类库进行修正
<!--[if IE 6]>
<script src="http://www.dillerdesign.com/experiment/DD_belatedPNG/DD_belatedPNG_0.0.8a.js"></script>
<script>
DD_belatedPNG.fix('*');//修正所有元素,如果你知道具体样式,可以传递样式名称进去
/* string argument can be any CSS selector */
/* .png_bg example is unnecessary */
/* change it to what suits you! */
</script>
<![endif]-->