function preload(n,s) {
  if (document.images) {
    eval(n+"=new Image();");		
    eval(n+".src='"+s+"';");
  }
}

function on(btn,comment) {
  if (document.images) document.images[btn].src = eval(btn+"_on.src")
}

function off(btn) {
  if (document.images) document.images[btn].src = eval(btn+"_off.src")
}


preload("menu_pozadi_on","images/menu_pozadi_aktivni.png");
preload("menu_pozadi_off","images/menu_pozadi_neaktivni.png");
preload("bus_menu_pozadi","images/bus_menu_pozadi.png");
preload("komentar_tlacitko_off","images/komentar_tlacitko_off.gif");