function calc_forward_fee(weight) {
	var forward_fee = new Array();

	forward_fee[0] = new Array();
	forward_fee[0]["weight_max"] = 500;
	forward_fee[0]["price"] = 490;
	forward_fee[1] = new Array();
	forward_fee[1]["weight_max"] = 1000;
	forward_fee[1]["price"] = 490;
	forward_fee[2] = new Array();
	forward_fee[2]["weight_max"] = 2000;
	forward_fee[2]["price"] = 980;
	forward_fee[3] = new Array();
	forward_fee[3]["weight_max"] = 3000;
	forward_fee[3]["price"] = 980;
	forward_fee[4] = new Array();
	forward_fee[4]["weight_max"] = 4000;
	forward_fee[4]["price"] = 1580;
	forward_fee[5] = new Array();
	forward_fee[5]["weight_max"] = 5000;
	forward_fee[5]["price"] = 1580;
	forward_fee[6] = new Array();
	forward_fee[6]["weight_max"] = 10000;
	forward_fee[6]["price"] = 1980;
	forward_fee[7] = new Array();
	forward_fee[7]["weight_max"] = 15000;
	forward_fee[7]["price"] = 2980;
	forward_fee[8] = new Array();
	forward_fee[8]["weight_max"] = 20000;
	forward_fee[8]["price"] = 2980;
	forward_fee[9] = new Array();
	forward_fee[9]["weight_max"] = 25000;
	forward_fee[9]["price"] = 3980;
	forward_fee[10] = new Array();
	forward_fee[10]["weight_max"] = 30000;
	forward_fee[10]["price"] = 3980;


	weight_min = 0;

//alert(forward_fee.length);
	for (var i = 0; i < forward_fee.length; i++) {
		var weight_max_int = parseInt(forward_fee[i]["weight_max"]);
		var weight_int = parseInt(weight);

		if (weight_min < weight_int && weight_int <= weight_max_int) {
			return forward_fee[i]["price"];
		}

//	for (var weight_max in forward_fee) {
//		weight_int = parseInt(weight);
//		weight_max_int = parseInt(weight_max);
//		if (weight_min < weight_int && weight_int <= weight_max_int) {
//			return forward_fee[weight_max];
//		}
		weight_min = weight_max_int;
	}
	return 0;
}