folder_dummy = ''; // obscure
	folder = '/jp/img/'
	var p_file = new Array(
		'navi_special','navi_research','navi_society','navi_software','navi_login','navi_logout','navi_registration','navi_upload','navi_forum',
		'navi_about','navi_inquiry','navi_faq','navi_sitemap','navi_link','lang_jump');
	var img = new Object();
	for (i=0;i<p_file.length;i++){
		img[p_file[i]] = new Image();
		img[p_file[i]+"_on"] = new Image();
		img[p_file[i]].src = folder + p_file[i] + '.gif';
		img[p_file[i]+"_on"].src = folder + p_file[i] + "_on.gif";
	}

	function On(name) {
		document.images[name].src = img[name+"_on"].src;
	}
	function Off(name) {
		document.images[name].src = img[name].src;
	}