var curMenu = '';

window.onload = function () {
  var menu = new Array('praxis', 'leistungen');  
  for (var i=0;i<menu.length;i++) {
    setEvent(menu[i], 'mouseover', showMenu);
  }
  document.onmouseover = hideMenu;  
}

function setEvent(id, strEvent, callbackFunction) {
  var obj = document.getElementById(id);
  if (obj.addEventListener) {
    obj.addEventListener(strEvent, callbackFunction, false); 
  } else if (obj.attachEvent){
    obj.attachEvent('on'+strEvent, callbackFunction);
  }
}

function showMenu(e) {
  if (!e) e = window.event;
  var objId = (e.srcElement)?e.srcElement.id:e.target.id;
  if (curMenu != '' && curMenu != objId) {
    document.getElementById(curMenu+'Menu').style.display = 'none';
  }
  var obj = document.getElementById(objId+'Menu');
  obj.style.display = 'block';
  curMenu = objId;
}

function hideMenu(e) {
  if (curMenu != '') {
    if (!e) e = window.event;
    var tag = (e.srcElement)?e.srcElement.tagName:e.target.tagName;
    if (tag != 'UL' && tag != 'LI' && tag != 'A') {
      document.getElementById(curMenu+'Menu').style.display = 'none';
      curMenu = '';
    }
  }
}