javascript - ie6 的工具提示问题

Question

我有一个带有伪类的工具提示。并且在所有浏览器上都可以正常工作。

但它不适用于ie6。我不知道它是否因为伪类而不起作用。我能得到任何帮助来使这项工作在 ie6 上运行吗？

span.tooltip {
    padding:0 5px;
    cursor:pointer;
    z-index:100;
    padding-top:2px
}
span.tooltip > span {
    display:none;
    background:#E4E8EF;
    top:-79px;
    left:18px;
    position:absolute;
    border-radius:5px;
    border:1px solid #BAC0C9;
    box-shadow:0 1px 4px #CAC9C9;
    z-index:100;
}
span.tooltip span b {
    display:block;
    width:262px;
    font-weight:normal;
    border-radius:5px;
    padding:10px 10px 10px;
    line-height:18px;
    color:#fff;
    position:relative;
    z-index:100;
    overflow:hidden;
    font-family:Arial, Helvetica, sans-serif;
    color:#1C3A54;
    font-size:12px
}
span.tooltip span b:before {
    display:block;
    content:"";
    width:100%;
    height:50px;
    position:absolute;
    left:10%;
    top:-30px;
    z-index:200;
}
span.tooltip:hover {
    position:relative;
    z-index:100;
}
span.tooltip:hover > span {
    display:block;
}

<span onmouseover="void(0)" class="tooltip"><img src="https://javasite.zones.internal/images/global/checkout/icon_question.png"><span><b>What you put in the Alias field will appear on the Ship To Address drop down list on your account so you can locate this address for future use.</b></span></span>

谢谢