isNS4 = (document.layers) ? true : false;
isIE4 = (document.all && !document.getElementById) ? true : false;
isIE5 = (document.all && document.getElementById) ? true : false;
isNS6 = (!document.all && document.getElementById) ? true : false;

function switchDiv(strDivName,bolVisible){

//identify the element based on browser type
if (isNS4) {
  objElement = document.layers[strDivName];
} else if (isIE4) {
  objElement = document.all[strDivName];
} else if (isIE5 || isNS6) {
  objElement = document.getElementById(strDivName);
}

if(isNS4){
    if(!bolVisible) {
      objElement.visibility ="hidden"
    } else {
      objElement.visibility ="visible"
    }     
}else{
    if(!bolVisible) {
      objElement.style.visibility = "hidden";
    } else {
      objElement.style.visibility = "visible";
    }
}
}