关于支付宝 错误代码 HAS_NO_PRIVILEGE的错误

具体的代码如下

<form id='alipaysubmit' name='alipaysubmit' action='https://mapi.alipay.com/gateway.do?_input_charset=utf-8' method='get'>
        <input type='hidden' name='_input_charset' value='utf-8' />
        <input type='hidden' name='body' value='商城所购商品' />
        <input type='hidden' name='defaultbank' value='ICBCB2C' />
        <input type='hidden' name='notify_url' value='http://xxxx.com/CN/pay/alipay_notify.aspx' />
        <input type='hidden' name='out_trade_no' value='20130621100239155' />
        <input type='hidden' name='partner' value='111111111' />
        <input type='hidden' name='payment_type' value='1' />
        <input type='hidden' name='paymethod' value='bankPay' />
        <input type='hidden' name='return_url' value='http://xxxx.com/a.aspx' />
        <input type='hidden' name='seller_email' value='123456@126.com' />
        <input type='hidden' name='service' value='create_direct_pay_by_user' />
        <input type='hidden' name='show_url' value='http://xxxxx.com/CN/a.aspx' />
        <input type='hidden' name='subject' value='商品' />
        <input type='hidden' name='total_fee' value='199.00' />
        <input type='hidden' name='sign' value='77778888877@wwww' />
        <input type='hidden' name='sign_type' value='MD5' />
        <input type='submit' value='确认' style='display: none;'/>
    </form>
    <script>document.forms['alipaysubmit'].submit();</script>

实在是搞不懂哪里错了

[解决办法]
可以问一下。name='sign' value='77778888877@wwww' sign 这个参数的值是怎么来的吗