function preLoadImgs(lang) {
  if(document.images) {
    preload_img=new Image();
    nav_imgs=new Array();
    nav_imgs[0]="/img/layout/navi/"+lang+"/home_h.gif";
    nav_imgs[1]="/img/layout/navi/"+lang+"/contact_h.gif";
    nav_imgs[2]="/img/layout/navi/"+lang+"/company_h.gif";
    nav_imgs[3]="/img/layout/navi/"+lang+"/assortment_h.gif";      
     
    var i=0;
    for(i=0;i<=3;i++) preload_img.src=nav_imgs[i];
  } 
}