Problem with firefox

i got problem with my php in firefox…

i seperate my menu file as “menu.php”…the codes looks like this…
“menu.php”
//menus
<table class=“menu” border=“0” cellspacing=“0” cellpadding=“0”>
<tr>
<td>
<a href=“index.php”>Home</a>
</td>
</tr>
<tr>
<td>
<a href=“contact.php”>Contact</a>
</td>
</tr>
</table>

the “menu.php” file is inside a table…the calling of the said file is inside a column of a table of my “index.php” file…
the “index.php” code looks like this…

<table class=“sample” border=“0” cellspacing=“0” cellpadding=“0”>
<tr>
<td>
<?
include (“menu.php”);
?>

&lt;/td&gt;

</tr>
</table>

there’s no problem with IE,it works perfectly as it is…but in FIREFOX, the menu which is a seperate file goes through the center of the page which destroys the whole page.and the class attributes of the css are change.
can you help me about this??..plssssssss…tnx