为什么我的 Android HttpClient 在调用 Execute 时不发送参数？

我有一个AsyncTask设置创建一个AndroidHttpClient并打电话Execute，有一个HttpPost and BasicHttpContext我提供的对象。我设置了HttpPost像这样：

HttpPost myPost = new HttpPost("http://192.168.1.66:8080/login.html");
BasicHttpParams httpParams = new BasicHttpParams();
httpParams.setParameter("cmd", "Login");
httpParams.setParameter("Username", "test");
httpParams.setParameter("Password", "password");
myPost.setParams(httpParams);

当我执行命令时，它检索的是登录页面而不是登录结果。在服务器端监控进程后，似乎这是因为HTTP请求到达时没有附加参数！那么我错过了什么？

            HttpPost post = new HttpPost("http://192.168.1.66:8080/login.html");
            List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(
                    3);
            nameValuePairs.add(new BasicNameValuePair("cmd", "Login"
                    .getText().toString()));
            nameValuePairs.add(new BasicNameValuePair("Username", "test"
                    .getText().toString()));

            nameValuePairs.add(new BasicNameValuePair("Password", "Password"
                    .getText().toString()));

            post.setEntity(new UrlEncodedFormEntity(nameValuePairs));