2悬停的背景在IE上不起作用

我想在一个li上使用2个不同的背景a：在水平菜单中悬停。它似乎在FF和铬工作，但不适用于IE。下面是使用CSS2悬停的背景在IE上不起作用

#layTopMenu 
{ 
    position: relative; 
    width: 970px; 
    height: 52px; 
    padding-top: 1px; 
    margin: 0 auto; 
    z-index: 5; 
} 
#layTopMenu ul 
{ 
    position: relative; 
    list-style: none; 
    margin: 0; 
    padding: 0; 
} 
#layTopMenu ul li 
{ 
    position: relative; 
    float: left; 
    margin: 0; 
    padding: 0 1px; 
    background: transparent url(../images/divider.gif) right no-repeat; 
} 
#layTopMenu ul li a { 
    color: #fff; 
    position: relative; 
    display: inline-block; 
    text-decoration: none; 
    margin: 0; 
    padding: 0 20px; 
    text-transform: uppercase; 
    text-align:center; 
    height: 49px; 
    line-height: 49px; 
} 
#layTopMenu ul li a:hover 
{ 
    color: #fff; 
    background:url(../images/nav_dot.gif) no-repeat center, url(../images/tab_hover_bg.gif) repeat-x; 
    text-align:center;  
    text-decoration: none; 
}

来源

2012-03-08 srilakshmi kethineni