function imgAct(imgName) {
    if (document.images) {
        document[imgName].src = eval(imgName + "on.src");
    }
}

function imgInact(imgName){
    if (document.images) { 
        document[imgName].src = eval(imgName + "off.src");
    }
}

function popupWindow(windowUrl,winName,features) { 
  window.open(windowUrl,winName,features);
}