DHTML/DOM appendChild() problem

function AddInputField(foo) {

  if (ns6) {
	ElementPresent = (document.getElementById('newInputField'))? true:false;
  }
  else if (ie4) {
	ElementPresent = (document.all["newInputField"])? true:false;
  }
  else if (ns4) {
	ElementPresent = (document.layers["newInputField"])? true:false;
  }

if (!ElementPresent) {
 var inputElement = document.createElement("input");
 inputElement.setAttribute("id","newInputField");
 inputElement.setAttribute("name","newInputField");
 
 var targetDiv = document.createElement("div");
 targetDiv.setAttribute("id","targetDiv");
	 		 
	 if (foo == "other") {
	 	if (ie4) {
		  document.all["select"].appendChild(targetDiv);
		  document.all["submitForm"].appendChild(inputElement);	
		}
		else if (ns4) {
		  document.layers["select"].appendChild(targetDiv);
		  document.layers["submitForm"].appendChild(inputElement);
		}	 
		else if (ns6) {
		document.getElementById('select').appendChild(targ  etDiv);
		document.getElementById('submitForm').appendChild(  inputElement);
		}	
	 }
 }
 else {
 	if (foo != "other") {	
	   if (ie4) {
		 var node1 = document.all["submitForm"];
	     var node2 = document.all["newInputField"];
         var exe = node1.removeChild(node2);
		}
		else if (ns4) {
		 var node1 = document.layers["submitForm"];
		 var node2 = document.layers["newInputField"];
		 var exe = node1.removeChild(node2);
		}	 
		else if (ns6) {
		  var node1 = document.getElementById('submitForm');
		  var node2 = document.getElementById('newInputField');
		  var exe = node1.removeChild(node2);
		}
	 }
   }
}