jQuery Grid Plugin - jqGrid

Posting this as a bug, as the behaviour is different in FF3 and IE6.

I'm having a problem using margin:auto to center the page. I found this problem on one of my own pages, but have managed to reproduce it using minimal changes to the code found at http://trirand.com/jqgrid/example.html

Added after html, body {…} :

body {
    margin:auto;
    width:800px;
}

Added:

<link href="/jquery/themes/jqModal.css" rel="stylesheet" type="text/css" />
<script type="text/javascript" src="/jquery/js/jqModal.js"></script>
<script type="text/javascript" src="/jquery/js/jqDnR.js"></script>

Changed:

        …
        sortorder: “desc”,
        caption: “Demo”
    }).navGrid('#pager2');
    });

This works as I expect in FireFox.  The body div is centered and stays centered.  (The grid appears slightly uncentered due to it not completely filling the div, but that isn't an issue for this test.)

In IE(6) however, while the body div is centered on load, clicking on any of the pager buttons which bring up an overlay and dialog moves the grid to the left side of the screen.

I'm hoping someone can confirm this as being a problem, as I can find no mention of body margins having to be set to fixed values in the documentation or the forums.