Menu control not working in IE6

[apgriffiths]

I have used a menu control and styled it using the CSS friendly control adapters along with a css file. When i view in IE7 or FF3 the menu works fine but when viewed in IE6 i do not get the second tier list items drop down.

Here is the css file used to style,

.myMenuCSS .AspNet-Menu-Horizontal
{
	position: relative;
	z-index: 300;
}
.myMenuCSS ul.AspNet-Menu /*Tier 1*/
{
	margin: 0;
	padding-left: 270px;
	/*padding-top: 20px;*/
	list-style: none;
}
.myMenuCSS ul.AspNet-Menu ul
{
	/*left: 0%;
	z-index: 400;
	list-style: none;*/
	width: 100px;
	background: #181A1C;
	left: 5px;
	top: 4em;
}
.myMenuCSS ul.AspNet-Menu ul li /*Tier 2 List Items*/
{
	width: 8.9em;
	float: left;
	clear: left;
	height: 100%;	
	display: inline;
}
.myMenuCSS ul.AspNet-Menu ul ul /*Tier 3*/
{
	top: 10em;
	left: 0.6em;
}
.myMenuCSS li /*All list items*/
{
	font-size: 12px;
	display: inline;
}
.myMenuCSS li:hover, /*list items hovered over*/
.myMenuCSS li.AspNet-Menu-Hover
{
	width: 100px;
	background: #DC8700;
	display: inline;
}
.myMenuCSS a, .myMenuCSS span
{
	display: block;
	float: left;
	height: 20px;
	margin: 0;
	padding: 18px 30px 18px 40px;
	background: url(images/img08.jpg) no-repeat left 30%;
	text-decoration: none;
	text-transform: capitalize;
	font-family: Georgia, "Times New Roman" , Times, serif;
	font-size: 10px;
	color: #FFFFFF;
}
.myMenuCSS li.AspNet-Menu-Leaf a, /*Leaves*/
.myMenuCSS li.AspNet-Menu-Leaf span
{
}

I have followed instructions on the adapters and put the following code in my master page head div,

<!--[if lt IE 7]>
    <link runat="server" rel="stylesheet"
        href="~/CSS/BrowserSpecific/IEMenu6.css" type="text/css">
    <link href="myMenuCSSIE6.css" rel="stylesheet" type="text/css" />
<![endif]-->

And the myMenuCSSIE6.css is as follows

.myMenuCSS ul.AspNet-Menu li /*Tier 1*/
{
	width: 1em;
	white-space: nowrap;
}
.myMenuCSS ul.AspNet-Menu ul li /*Tier 2 list items*/
{
	white-space: normal;
}

Do i need to add some more code to this IE6 file to make the menu work?

Not sure how i solve this, any help is much appreciated.