Oops I missed the "Hi" being in there. You have a line break after the "Hi" and then your form. Place that all on one line.
HTML Code:
<html>
	<body>
		<table border=1>
			<tr>
				<td>hi<form><input type=hidden value='hello' height=0></form></td>
			</tr>
		</table>
	</body>
</html>