Menu dropdown placement incorrect

hello
i have managed to get a working menu where i want it and have managed to have a fixed header and footer. however, i have a problem when the main page scrolls the dropdown menu seems to scroll with it. instead of the dropdown being below the heading where it normally is, if i scroll the page the header and footer stay where they are but if i click the menu heading again, the dropdown is halfway down the page. i have attached css and the correct and incorrect screenshots to give you an idea if my outline is fuzzy. i would be grateful if someone could tell me where i am going wrong? i am only learning css and would be grateful for any advice. many thanks

CSS CODE

body
{

margin: 0px;
padding: 0px;
font-family: Arial;
}
/* Don't touch */
ul#jmenu
{

margin: 0px;
padding: 0px;
list-style: none;
}
ul#jmenu li
{

float: left;
margin: 0px;
padding: 0px;
//width: 1px; /* ie */
//vertical-align: bottom;  /* ie */
}
ul#jmenu li a
{

display: block;
white-space: nowrap;
}

ul#jmenu li ul
{
display: none;
position: absolute;
margin: 0px;
padding: 0px;
list-style: none;
zoom: 1;  /* ie */
}
ul#jmenu li ul li
{
float: none;
}

/* Styling starts here */
ul#jmenu
{


margin-top:80px;
width: 100%;
height: 40px;
background: #3f4a58 url('../images/menu-bg.gif') repeat-x left top;
}
ul#jmenu li
{
background: url('../images/separator.gif') no-repeat right center;
padding: 0px 10px;
}
ul#jmenu li a:link, ul#jmenu li a:visited
{

padding: 0px 10px;
height: 40px;
line-height: 40px;
color: #e4ecf6;
font-size: 13px;
text-decoration: none;
background: none;
}
ul#jmenu li a:hover
{

color: #ffffff;
background: #3f4a58 url('../images/menu-bg.gif') repeat-x left bottom;
margin-top:0px;
}
ul#jmenu ul
{
background-color: #3f4a58;
border-left: 1px solid #7a8087;
}
ul#jmenu li ul li
{
padding: 0px;
background: url('../images/sub-separator.gif') repeat-x left bottom;
}
ul#jmenu li ul li a:link, ul#jmenu li ul li a:visited
{
;
min-width: 100px;
//width: 100px;  /* ie */
font-size: 12px;
height: 30px;
line-height: 30px;
}
ul#jmenu li ul li a:hover
{

background: #3f4a58 url('../images/menu-bg.gif') repeat-x left top;
}
#header {
			position:fixed;
			width:100%;
			left:0px;
			top:0px;
			height: 80px;
			background: #808080 url(../../images/logo.jpg) no-repeat left center;
			
			
			
}
#logo 	{
			
			/*background-image:url(../../images/logo.jpg) no-repeat left;*/
			
		}


#footer {
			position:fixed;
			left:0px;
			bottom:0px;
			height:30px;
			width:100%;
			background:#808080;
			border-top:1px solid #333333;
		}
.footertext {
			font-family: Verdana, Arial, Helvetica, sans-serif;
			font-size: 12px;
			color: #FFFFFF;
			margin:10px;
			display:block; 
			}
	
/* IE 6 */
* html #footer {
   position:absolute;
   top:expression((0-(footer.offsetHeight)+(document.documentElement.clientHeight ? document.documentElement.clientHeight : document.body.clientHeight)+(ignoreMe = document.documentElement.scrollTop ? document.documentElement.scrollTop : document.body.scrollTop))+'px');
}
#main{
	font-family: Verdana, Arial, Helvetica, sans-serif;
	font-size: 12px;
	height:100%;
	margin-top:25px;
	}
#main p  	{
	margin-left:20px;
	
	font-family: Verdana, Arial, Helvetica, sans-serif;
	font-size: 12px;
	}

HTML CODE

<div id="header">
		<ul id="jmenu">
			<li><a href="#">Home</a></li>
			<li>
			<a href="#">Requests</a>
			<ul>
            <li><a href="#">Item 2-1</a></li>
            <li><a href="#">Item 2-2</a></li>
            <li>
            <a href="#">Item 2-3</a>
         <ul>
            <li><a href="#">Item 2-3-1</a></li>
            <li>
            <a href="#">Item 2-3-2</a>
         <ul>
            <li><a href="#">Item 2-3-2-1</a></li>
         </ul>
            </li>
            <li><a href="#">Item 2-3-3</a></li>
         </ul>
            </li>
            <li>
            <a href="#">Item 2-4</a>
         <ul>
            <li><a href="#">Item 2-4-1</a></li>
            <li><a href="#">Item 2-4-2</a></li>
            <li><a href="#">Item 2-4-3</a></li>
          </ul>
            </li>
            <li><a href="#">Item 2-5</a></li>
        </ul>
    		</li>
    		<li><a href="#">Reports</a></li>
    		<li>
        	<a href="#">Control Panel</a>
        <ul>
            <li><a href="#">Item 4-1</a></li>
            <li><a href="#">Item 4-2</a></li>
            <li><a href="#">Item 4-3</a></li>
        </ul>
    		</li>
   			 <li>
   			   <?php
	echo $tNGs->getErrorMsg();
?><a href="<?php echo $logoutTransaction->getLogoutLink(); ?>">Logout</a></li>
		</ul>
		</div></div>

You seem to be missing some code.

Where is the code to make the submenu appear? I only see that it’s set to display: none.