if(document.images) {
	var imgs = new Array();
	imgs[2] = new Image();  imgs[2].src = "img/gnavi_about_off.gif";
	imgs[3] = new Image();  imgs[3].src = "img/gnavi_about_on.gif";
	imgs[4] = new Image();  imgs[4].src = "img/gnavi_blog_off.gif";
	imgs[5] = new Image();  imgs[5].src = "img/gnavi_blog_on.gif";
	imgs[6] = new Image();  imgs[6].src = "img/gnavi_contact_off.gif";
	imgs[7] = new Image();  imgs[7].src = "img/gnavi_contact_on.gif";
	imgs[8] = new Image();  imgs[8].src = "img/gnavi_works_off.gif";
	imgs[9] = new Image();  imgs[9].src = "img/gnavi_works_on.gif";
	imgs[10] = new Image();  imgs[10].src = "img/btn_pagetop_off.gif";
	imgs[11] = new Image();  imgs[11].src = "img/btn_pagetop_on.gif";
	imgs[12] = new Image();  imgs[12].src = "img/contact_email_off.gif";
	imgs[13] = new Image();  imgs[13].src = "img/contact_email_on.gif";

}
function chgimg(id, imgname) {
	if(document.images) {
		if(imgs[imgname]) {
			document.images[id].src = imgs[imgname].src;
		}
		else {
			document.images[id].src = imgname;
		}
	}
}