Set <td> width using dhtml which runs in Netscape

hi ,
how can i set width for a <td> which should work in netscape, which i am generating dynamically

using Javascript. This is the code i have used, the width i set is working in IE, but it is not

working in Netscape. Hope u guys will give me a solution.

<script language="javascript">
id="displaytable";
var tbody = document.getElementById(id).getElementsByTagName("TBODY")[0];

var rowempty = document.createElement("TR");
rowempty.setAttribute("id","tr"+counter);

var row1= document.createElement("TR");
row1.setAttribute("id","tr"+counter);

var tdf1 = document.createElement("TD");
td1.setAttribute("width","42%");
td1.innerHTML="First Name"

row1.appendChild(td1);

tbody.appendChild(row1);
</script>
Thank u
Sujay