var windowOst;
function openPopupKontakt()
{
  windowOst = window.open("kontakt.php",
                  "Kontakt",
                  "height=560,width=690,resizable=yes,scrollbars=yes,status=yes");
  windowOst.focus();
}

var windowContact;
function openPopupContact()
{
  windowContact = window.open("kontakt_eng.php",
                  "Contact",
                  "height=560,width=690,resizable=yes,scrollbars=yes,status=yes");
  windowContact.focus();
}