if (document.images) {

  var apln = new Image();
  apln.src = "img/buttons/application_1.gif";
  var apla = new Image();
  apla.src = "img/buttons/application_2.gif";

  var vacn = new Image();
  vacn.src = "img/buttons/vacancies_1.gif";
  var vaca = new Image();
  vaca.src = "img/buttons/vacancies_2.gif";

  var conn = new Image();
  conn.src = "img/buttons/contacts_1.gif";
  var cona = new Image();
  cona.src = "img/buttons/contacts_2.gif";

  var newn = new Image();
  newn.src = "img/buttons/news_1.gif";
  var newa = new Image();
  newa.src = "img/buttons/news_2.gif";
  }

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

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