HTML table cells aren't uniform width in Firefox, fine in Chrome and IE8

I'm working on an app in ASP.NET MVC 2, and the output of the table looks the way I'd expect in Chrome and IE8:

but this is how it looks in FF 3.6.8 it looks like this:

I'm using Javascript开发者_JAVA百科/jQuery to add rows, this is the code:

        function onAddItem() {
        itemCount = itemCount + 1;
        var rowString = "<tr id=" + itemCount + ">";
        rowString = rowString + "<td>" + document.getElementById("Order_productcode").value + "</td>";
        rowString = rowString + "<td>" + document.getElementById("Order_productsku").value + "</td>";
        rowString = rowString + "<td>" + document.getElementById("Order_productdesc").value + "</td>";
        rowString = rowString + "<td align=\"right\">" + document.getElementById("ItemQuantity").value + "</td>";
        rowString = rowString + "<td>" + document.getElementById("Order_productweight").value + "</td>";
        rowString = rowString + "<td>" + document.getElementById("Order_productcost").value + "</td>";
        rowString = rowString + "</tr>";
        $row = $(rowString);
        $row.hide().fadeIn("slow").appendTo("#orderedItems table tbody");
    }

Looking in Firebug, I found the row that gets created looks like this:

 <tr style="display: block;" id="1"><td>EC5931A-Tote</td><td>100002</td><td></td><td align="right"></td><td>0</td><td>33250.00</td></tr></tbody>

that is, it adds style="display: block;", which seems to be the problem (when I edited it out in Firebug, it looked correct, i.e., like in IE and Chrome). Why is Firefox doing that, and how can I make it stop?

EDIT: I removed the .hide().fadeIn("slow") and now it's working correctly in Firefox. Seems to be a bug in jQuery with Firefox, although I didn't see it on the jQuery site.