IE6/7BUG之overflow:hidden无效

BUG描述：

当父容器设置了OVERFLOW：hidden,子元素比父容器高（宽）部分在正常情况是不显示的，而

IE6/7由于这个BUG显示了子元素的过大的部分

BUG代码

<div class="container">
    <img src="RelPosChildNotClippedByParentOverflowHidden.png"
         width="300"
         height="300"
         alt="">
</div>

<div class="container">
    <div id="block"></div>
</div>

.container {
    height: 200px;
    width: 200px;
    overflow: hidden;
    border: 5px solid #000;
}

#block {
    width: 300px;
    height: 300px;
    background: url(RelPosChildNotClippedByParentOverflowHidden.png);
}

#block, img {
    position: relative;
}

BUG截图（IE6）如下：

BUG解决：

为父元素添加样式：POSITION:RELATIVE

.container {
    margin-bottom: 150px;
    height: 200px;
    width: 200px;
    overflow: hidden;
    border: 5px solid #000;
    position: relative;
}

#block {
    width: 300px;
    height: 300px;
    background: url(RelPosChildNotClippedByParentOverflowHidden.png);
}

#block, img {
    position: relative;
}