if (document.images) {
  corporateon = new Image();
  corporateon.src = "images/menu/btn_corporate_on.gif";
  corporateoff = new Image();
  corporateoff.src = "images/menu/btn_corporate_off.gif";
  
  serviceson = new Image();
  serviceson.src = "images/menu/btn_services_on.gif";
  servicesoff = new Image();
  servicesoff.src = "images/menu/btn_services_off.gif";
  
  qualityon = new Image();
  qualityon.src = "images/menu/btn_quality_on.gif";
  qualityoff = new Image();
  qualityoff.src = "images/menu/btn_quality_off.gif";
  
  facilityon = new Image();
  facilityon.src = "images/menu/btn_facility_on.gif";
  facilityoff = new Image();
  facilityoff.src = "images/menu/btn_facility_off.gif";
  
  careerson = new Image();
  careerson.src = "images/menu/btn_careers_on.gif";
  careersoff = new Image();
  careersoff.src = "images/menu/btn_careers_off.gif";
  
  rfqon = new Image();
  rfqon.src = "images/menu/btn_rfq_on.gif";
  rfqoff = new Image();
  rfqoff.src = "images/menu/btn_rfq_off.gif";
  
  contacton = new Image();
  contacton.src = "images/menu/btn_contact_on.gif";
  contactoff = new Image();
  contactoff.src = "images/menu/btn_contact_off.gif";
  
}


function changeImages() {
  if (document.images) {
    for (var i=0; i<changeImages.arguments.length; i+=2) {
      document[changeImages.arguments[i]].src = eval(changeImages.arguments[i+1] + ".src");
    }
  }
}