VPN connection from Android emulator fails

I am new to Android development. I am trying to join an existing VPN from my Android app. I want to integrate the VPN in my app; my app then is supposed to query a remote database.

I got some code and tried to use it to create a VPN. It emulates the built-in VPN manager on the Android phone. The code compiles and the manager is launched but the connection to the VPN does not succeed when I try to connect after all configuration. The protocol is PPTP. A VPN exists and has been tested.

I tried connecting from an android phone with the same settings and it was successful.

I thought maybe I am passing the parameters in the wrong way. I have put the code for the vpn part below. The url is not the actual but in same format.

Any help to identify what I am doing wrong would be appreciated. Also if there is a way I can directly call the VPN manager from my app.

Thanks very much for any help,

final Button button1 = (Button)findViewById(R.id.button1);
final Button button2 = (Button)findViewById(R.id.button2);
final Button button3 = (Button)findViewById(R.id.button3);


    button1.setOnClickListener(new View.OnClickListener() {
                            public void onClick(View v) {
            startActivity(new Intent("android.net.vpn.SETTINGS"));
        }
    });

    button2.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            URL url = null;
            try {
                String registrationUrl = String.format("daffy.zune.org");
                url = new URL(registrationUrl);
                URLConnection connection = url.openConnection();
                HttpURLConnection httpConnection = (HttpURLConnection) connection;
                int responseCode = httpConnection.getResponseCode();
                if (responseCode == HttpURLConnection.HTTP_OK) {
                    Log.d("MyApp", "Registration success");
                } else {