function over(n) {newImage = "url(on.gif)";document.getElementById('tab'+n).style.backgroundImage = newImage;}
function off(n) {newImage = "url(off.gif)";document.getElementById('tab'+n).style.backgroundImage = newImage;}

function overh(n) {newImage = "url(on.gif)";document.getElementById('htab'+n).style.backgroundImage = newImage;}
function offh(n) {newImage = "url(off.gif)";document.getElementById('htab'+n).style.backgroundImage = newImage;}