Drop Down Menu within a Menu Include Page

Hi
hope someone can help!
I've added the code below into my menu include page and it works ok when in Browser.
I now want to add this page as a menu include into my main page but the dropdown menu then doesnt doest work! Is there a bit of code I need to add in my main page to activate the dropdown menu?

Code within the head,

#popitmenu{
position: absolute;
background-color: white;
border:1.5px solid black;
font: normal 11px arial;
line-height: 20px;
z-index: 500;
visibility: hidden;
}

#popitmenu a{
text-decoration: none;
padding-left: 6px;
color: black;
display: block;
}

#popitmenu a:hover{ /*hover background color*/
background-color: lightblue;
}


#dhtmltooltip{
position: absolute;
width: 4500px;
border: 1px solid black;
padding: 1px;
background-color: white;
visibility: hidden;
z-index: 100;
/*Remove below line to remove shadow. Below line should always appear last within this CSS*/
filter: progid:DXImageTransform.Microsoft.Shadow(color=white,direction=135);
}



</style>


<script type="text/javascript">

/***********************************************
* Pop-it menu- © Dynamic Drive (www.dynamicdrive.com)
* This notice MUST stay intact for legal use
* Visit http://www.dynamicdrive.com/ for full source code
***********************************************/

var defaultMenuWidth="150px" //set default menu width.

var linkset=new Array()
//SPECIFY MENU SETS AND THEIR LINKS. FOLLOW SYNTAX LAID OUT


linkset[1]='<a href="http://"">Title</a>'
linkset[1]+='<a href="http://"">Title</a>'


////No need to edit beyond here

var ie5=document.all && !window.opera
var ns6=document.getElementById

if (ie5||ns6)
document.write('<div id="popitmenu" onMouseover="clearhidemenu();" onMouseout="dynamichide(event)"></div>')

function iecompattest(){
return (document.compatMode && document.compatMode.indexOf("CSS")!=-1)? document.documentElement : document.body
}

function showmenu(e, which, optWidth){
if (!document.all&&!document.getElementById)
return
clearhidemenu()
menuobj=ie5? document.all.popitmenu : document.getElementById("popitmenu")
menuobj.innerHTML=which
menuobj.style.width=(typeof optWidth!="undefined")? optWidth : defaultMenuWidth
menuobj.contentwidth=menuobj.offsetWidth
menuobj.contentheight=menuobj.offsetHeight
eventX=ie5? event.clientX : e.clientX
eventY=ie5? event.clientY : e.clientY
//Find out how close the mouse is to the corner of the window
var rightedge=ie5? iecompattest().clientWidth-eventX : window.innerWidth-eventX
var bottomedge=ie5? iecompattest().clientHeight-eventY : window.innerHeight-eventY
//if the horizontal distance isn't enough to accomodate the width of the context menu
if (rightedge<menuobj.contentwidth)
//move the horizontal position of the menu to the left by it's width
menuobj.style.left=ie5? iecompattest().scrollLeft+eventX-menuobj.contentwidth+"px" : window.pageXOffset+eventX-menuobj.contentwidth+"px"
else
//position the horizontal position of the menu where the mouse was clicked
menuobj.style.left=ie5? iecompattest().scrollLeft+eventX+"px" : window.pageXOffset+eventX+"px"
//same concept with the vertical position
if (bottomedge<menuobj.contentheight)
menuobj.style.top=ie5? iecompattest().scrollTop+eventY-menuobj.contentheight+"px" : window.pageYOffset+eventY-menuobj.contentheight+"px"
else
menuobj.style.top=ie5? iecompattest().scrollTop+event.clientY+"px" : window.pageYOffset+eventY+"px"
menuobj.style.visibility="visible"
return false
}

function contains_ns6(a, b) {
//Determines if 1 element in contained in another- by Brainjar.com
while (b.parentNode)
if ((b = b.parentNode) == a)
return true;
return false;
}

function hidemenu(){
if (window.menuobj)
menuobj.style.visibility="hidden"
}

function dynamichide(e){
if (ie5&&!menuobj.contains(e.toElement))
hidemenu()
else if (ns6&&e.currentTarget!= e.relatedTarget&& !contains_ns6(e.currentTarget, e.relatedTarget))
hidemenu()
}

function delayhidemenu(){
delayhide=setTimeout("hidemenu()",500)
}

function clearhidemenu(){
if (window.delayhide)
clearTimeout(delayhide)
}

if (ie5||ns6)
document.onclick=hidemenu

</script>
</head>

Code wihtin the body
<a href="#" onMouseover="showmenu(event,linkset[1], '180px')" onMouseout="delayhidemenu()"><font face="Frutiger 55 Roman" size="3" color="#0079C6"><b>Title</b></font></a>

Kind Regards
Jude