IE vs. Firefox dialog scrollbar issue

IE vs. Firefox dialog scrollbar issue


Version Info:
jquery 1.3.2
jquery ui 1.7.2 (ui lightness theme)
Firefox 3.5.2
IE 8
I have created a modal dialog with jquery ui. The issue is that in
Internet Explorer the height of the dialog is larger than my height
and maxHeight options, and no scrollbar appears.
In Firefox, it is displayed correctly.
Any help is appreciated, as I am under the gun to get a project out
this weekend!
Here is a link to my sample page to see the problem:
http://www.bigchill.com/examples/testdialog2.html
Here is the code I am using to create the dialog:
        // create categories modal dialog
        $("#dialog").dialog({
         bgiframe: true,
            width: 800,
            height: 500,
            maxHeight: 500,
            autoOpen: false,
            draggable: false,
            resizable: false,
            modal: true,
            buttons: {
                'Set Categories': function() {
                    $(this).dialog('close');
                }
            }
        });
Thanks,
Jim Spencer