Problema con DOM

[SilentHill]

Probe antes pasarlo como vos dijiste pero tampoco lo respecta el FF, les muestro el code como esta hoy:

Código:

<script language="javascript">
	var a = 0;
	function cantidad (id)
	{
		if (document.forms[0].pjs.value != 0)
		{
			var tbody = document.getElementById(id).getElementsByTagName("TBODY")[0];
			if (a>0)
			{
				for(w=0;w<a;w++)
				{
				tbody.removeChild(document.getElementById('raw'+w) );
				tbody.removeChild(document.getElementById('raw2'+w) );
				}
			}
			for (a=0;a<document.forms[0].pjs.value;a++)
			{
				var row = document.createElement("TR");
				row.id = "raw" + a;
				var td1 = document.createElement("TD");
				td1.style.width = "700px";
				td1.appendChild(document.createTextNode("Personaje:"));
				var td2 = document.createElement("TD");
				td2.style.width = "15px";
				var img1 = document.createElement("IMG");
				img1.src="system/images/empty.gif";
				img1.width = "0";
				td2.appendChild(img1);
				var td3 = document.createElement("TD");
				var input1 = document.createElement("INPUT");
				input1.type = "text";
				input1.name = "pj" + a;
				td3.appendChild(input1);
				var td4 = document.createElement("TD");
				td4.style.width = "20px";
				var td5 = document.createElement("TD");
				td5.style.width = "20px";
				td5.appendChild(document.createTextNode("Nivel:"));
				var td6 = document.createElement("TD");
				td6.style.width = "15px";
				var img2 = document.createElement("IMG");
				img2.src="system/images/empty.gif";
				img2.width = "0";
				td6.appendChild(img1);
				var td7 = document.createElement("TD");
				var input2 = document.createElement("INPUT");
				input2.type = "text";
				input2.name = "pj" + a;
				td7.appendChild(input2);
				var row2 = document.createElement("TR");
				row2.id = "raw2" + a;
				var td8 = document.createElement("TD");
				td8.height = "5px";
				td8.colspan = "7"; 
				row.appendChild(td1);
				row.appendChild(td2);
				row.appendChild(td3);
				row.appendChild(td3);
				row.appendChild(td4);
				row.appendChild(td5);
				row.appendChild(td6);
				row.appendChild(td7);
				row2.appendChild(td8);
				tbody.appendChild(row);
				tbody.appendChild(row2);
			}
		}
	}
</script>

Saludos