Refresh DIV seems to cause memory leak problem in IE

Refresh DIV seems to cause memory leak problem in IE

I have this code to refesh a DIV on my pages but if Internet Explorer
is left running all day, it eats up all available memory to the point
where the computer hangs.
This is the code:
var refreshId = setInterval(function() {
$('#footerBar').load('liveTasksFeed.php');
}, 5000);
This is the DIV code:
<div id="footerBar">Loading...</div>
Basicaly the contents of liveTasksFeed.php replaces the Loading....
message after 5 seconds and the liveTasksFeed.php has a recordset
query which checks for any records that have a date and time of NOW()
to enable the task funcioanlity.
On the liveTasksFeed.php I have the following jQuery elements:
<script type="text/javascript" src="js/jquery-1.3.2.min.js"></script>
<script type="text/javascript" src="js/jquery-
ui-1.7.2.custom.min.js"></script>
<link href="css/ui-lightness/jquery-ui-1.7.2.custom.css"
rel="stylesheet" type="text/css" />
<?php if ($totalRows_rsTasks > 0) { // Show if recordset not empty ?>
Logged in as: <strong>Lee Bridgewater</strong> ( Total tasks which are
currently open to you <strong>0 </strong>)
<a href="logOut.php">Log Out</a>
<script type="text/javascript">
    $(document).ready(function() {
        $("#dialog").dialog({
            bgiframe: true,
            height: 450,
            modal: true
        });
    });
    </script>
Is this the correct way to implement this?
Basicaly all I want to do is display a mocal dialog box on the page
whenever a record is called matching the current date/time.
Any help appreciated.
Thanks
Lee
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