var NS4 = (document.layers)?true:false;
var MSIE = (document.all)?true:false;
var NS6 = (navigator.userAgent.indexOf("Gecko")>0)?1:0;
var validdata;

function exclusiveCheckedDue(cbx1, cbx2) {
   if (document.getElementById(cbx1).checked == true)
      document.getElementById(cbx2).checked = false;
   }

function exclusiveCheckedTre(cbx1, cbx2, cbx3) {
   if (document.getElementById(cbx1).checked == true){
      document.getElementById(cbx2).checked = false;
			document.getElementById(cbx3).checked = false;
			}
   }	 
	 
function exclusiveCheckedQuattro(cbx1, cbx2, cbx3, cbx4) {
   if (document.getElementById(cbx1).checked == true){
      document.getElementById(cbx2).checked = false;
			document.getElementById(cbx3).checked = false;
			document.getElementById(cbx4).checked = false;
			}
   }