function GetEventTarget(event)
{
  if (!event) {
    event = window.event;
  }

  if (event.target) {
    object = event.target;
  } else {
    object = event.srcElement;
  }
  return object;
}

function OnEnterMenuItem(event)
{
  var object = GetEventTarget(event);
  object.style.backgroundImage = "url(images/menu_highlight.png)"
 	object.style.backgroundPosition ="top left"
}

function OnLeaveMenuItem(event)
{
  var object = GetEventTarget(event);
  object.style.backgroundImage = "none";
}

function OnMenuItemClick(event)
{  
  var object = GetEventTarget(event);
  object.style.backgroundImage = "none";
  window.location = object.id + ".html"  
}

function GetIEVersion()
{
  var version = -1;

  if (window.navigator.appName == "Microsoft Internet Explorer") {
    var user_agent = navigator.userAgent;
    var reg_expresion = new RegExp("MSIE ([0-9]{1,}[\.0-9]{0,})");
    if (reg_expresion.exec(user_agent) != null) {
      version = parseFloat(RegExp.$1);
    }
  }
  return version;
}

function TestIE()
{
  var ie_version = GetIEVersion();
  if (ie_version == -1) {
    return;
  }
  if (ie_version < 7) {
    window.location = "ie_version.html" 
  }
}