var imageDir = _imgdir;
	var preLoadList;
	var action = "false";

	function preLoad(){
		preLoadList = new Array(
			"navi_member_entry.gif","navi_member_entry_e.gif",
			"navi_member_campaign.gif","navi_member_campaign_e.gif",
			"navi_btn_login.gif","navi_btn_login_e.gif",
			"btn_login_02.gif","btn_login_02_e.gif",
			"pic_fee_bid_0001.gif","pic_fee_bid_0001_e.gif",
			"pic_fee_bid_0002.gif","pic_fee_bid_0002_e.gif",
			"pic_fee_bid_0003.gif","pic_fee_bid_0003_e.gif");
		onImages = new Array();
		for(field in preLoadList){
			onImages[field] = new Image();
			onImages[field].src = imageDir + preLoadList[field];
		}
		action = "true";
	}

	function changeImage(fileName, imageName){
		if (action == "true"){
			document.images[imageName].src = imageDir + fileName;
		}
	}