Applet not initialized

I have compiled the following code and it compiles but when i run the code the following error message is shown in the applet window Start: Applet not initialized. Can someone have a look at my code and say where I went wrong. Thanks

import java.awt.*;
import javax.swing.*;
import javax.swing.JApplet;
/*
* Created on Feb 12, 2005
*
*/

/**
* @author trixma
* @version 1.0
*/
public class IPClassFinder extends JApplet {
private Container container;
private JLabel ipClass, header, title, fullstop, fullstop1, fullstop2;
private JButton calculate, clear;
private JTextField field1, field2, field3, field4, field5;

public void init() {

container = getContentPane();

JPanel border = new JPanel(new BorderLayout(5,5));

header = new JLabel("IP address information", JLabel.CENTER);
border.add(header);

JPanel grid1 = new JPanel();
grid1.setLayout(new GridLayout(2,8,1,5));

title = new JLabel("Enter IP Address", JLabel.CENTER);
grid1.add(title);

field1 = new JTextField(3);
grid1.add(field1);

fullstop = new JLabel(".", JLabel.CENTER);
grid1.add(fullstop);

field2 = new JTextField(3);
grid1.add(field2);

fullstop1 = new JLabel(".", JLabel.CENTER);
grid1.add(fullstop1);

field3 = new JTextField(3);
grid1.add(field3);

fullstop2 = new JLabel(".", JLabel.CENTER);
grid1.add(fullstop2);

field4 = new JTextField(3);
grid1.add(field4);

ipClass = new JLabel("IP Address Class");
grid1.add(ipClass);

field5 = new JTextField();
grid1.add(field5);

border.add("CENTER", grid1);

JPanel grid2 = new JPanel(new GridLayout(1,2,5,5));

calculate = new JButton("Calculate");
grid2.add(calculate);

clear = new JButton("Clear");
grid2.add(clear);

border.add("South", grid2);

container.add(border);

}
}

Below is the solution to the above problem.

JPanel border = new JPanel(new BorderLayout(5,5)); <-- deleted this line

border.add(header); <- this line should be container.add(header, BorderLayout.NORTH);

border.add("CENTER", grid1); <- This line should be container.add(grid1, BorderLayout.CENTER);

border.add("South", grid2); <- This line should be container.add(grid2, BorderLayout.SOUTH);

container.add(border); <- deleted this line

also, you may delete import javax.swing.JApplet; as it is already imported via import javax.swing.*;