function menu(obj)
{
if(obj.status == undefined) { // poprvé spuštěna tato funkce
obj.onmouseout = function() {menu(obj);};
obj.status = "out";
}

if(obj.status == "out") {obj.status = "on";}
else{obj.status = "out";};

if(obj.status == "on")
{  obj.style.backgroundImage = "url('img_bunka_on.gif')";}
else{    obj.style.backgroundImage = "url('img_bunka.gif')";};
};

function popup(url)
{
window.open(url);
return true;
};