function check_browser()
{
  var version_number = navigator.appVersion.charAt(0);

  if (navigator.appName.indexOf("Netscape") != -1)
  {
    if (version_number < 3)
    {
      return false;
    }
    return true;
  }

  if (navigator.appName.indexOf("Explorer") != -1)
  {
    if (version_number < 4)
    {
      return false;
    }
    return true;
  }

  // unknown
  return false;
}


  if (check_browser()) 
{  
  <!--menu-->
  HEAD1 = new Image(125,45);
  HEAD2 = new Image(102,45);
  HEAD3 = new Image(92,45);
  HEAD4 = new Image(100,45);
  HEAD5 = new Image(100,45);
 
  MAIN1 = new Image(178,25);
  MAIN2 = new Image(178,25);
  MAIN3 = new Image(178,25);
  MAIN4 = new Image(178,25);
  MAIN5 = new Image(178,25);
  MAIN6 = new Image(178,25);
  MAIN7 = new Image(178,25);
  MAIN8 = new Image(178,25);
  MAIN9 = new Image(178,25); 
   
  HEAD1on = new Image(125,45);
  HEAD2on = new Image(102,45);
  HEAD3on = new Image(92,45);
  HEAD4on = new Image(100,45);
  HEAD5on = new Image(100,45);
  
  MAIN1on = new Image(178,25);
  MAIN2on = new Image(178,25);
  MAIN3on = new Image(178,25);
  MAIN4on = new Image(178,25);
  MAIN5on = new Image(178,25);
  MAIN6on = new Image(178,25);
  MAIN7on = new Image(178,25);
  MAIN8on = new Image(178,25);  
  MAIN9on = new Image(178,25); 
  
  BLANK = new Image(118,13);

  
  HEAD1.src = "img/top/contactUs.gif";
  HEAD2.src = "img/top/aboutUs.gif";
  HEAD3.src = "img/top/advertise.gif";
  HEAD4.src = "img/top/terms.gif";
  HEAD5.src = "img/top/support.gif";

  

  MAIN1.src = "img/side/shoppingMall.gif";
  MAIN2.src = "img/side/artDesign.gif";
  MAIN3.src = "img/side/business.gif";
  MAIN4.src = "img/side/education.gif";
  MAIN5.src = "img/side/fashion.gif";
  MAIN6.src = "img/side/living.gif";
  MAIN7.src = "img/side/money.gif";
  MAIN8.src = "img/side/nyNow.gif";
  MAIN9.src = "img/side/topics.gif";
  
  HEAD1on.src = "img/top/contactUsD.gif";
  HEAD2on.src = "img/top/aboutUsD.gif";
  HEAD3on.src = "img/top/advertiseD.gif";
  HEAD4on.src = "img/top/termsD.gif";
  HEAD5on.src = "img/top/supportD.gif";


  
  MAIN1on.src = "img/side/shoppingMallD.gif";
  MAIN2on.src = "img/side/artDesignD.gif";
  MAIN3on.src = "img/side/businessD.gif";
  MAIN4on.src = "img/side/educationD.gif";
  MAIN5on.src = "img/side/fashionD.gif";
  MAIN6on.src = "img/side/livingD.gif";
  MAIN7on.src = "img/side/moneyD.gif";
  MAIN8on.src = "img/side/nyNowD.gif";
  MAIN9on.src = "img/side/topicsD.gif";

  BLANK.src = "img/blank.gif"
}