Qualcuno ha una mezza idea del perchè quando mando in eseguzione questo codice il frame è della grandezza corretta mentre il jTextPane rimane piccolo.
Per chi desidera provarlo sono 3 classi..Gui che contiene il jTextPane, il main per farlo partire e WHandler per chiudere la finestra...

Help...
codice:
    

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

/*Create windows */
public class Gui extends JFrame {
	private GridBagLayout gbl;
	private JPanel contentPanA;
	public JTextPane console;
	private Menu menuFile;
	private Menu menuText;
	private MenuBar mb;
	public String font;
	public int style;
	public int size; 
 
 
  public Gui() {
    super("Console");
    
   
   
    console = new JTextPane();
    console.setMargin(new Insets(5,5,5,5));
    
    gbl = new GridBagLayout();
    contentPanA = new JPanel(gbl);
    GridBagConstraints c = new GridBagConstraints();
    /*for resize console with pannel*/
    c.fill = GridBagConstraints.BOTH;
    c.weightx = 1.0;
    c.weighty = 1.0;
    
    c.gridwidth = GridBagConstraints.REMAINDER;
    addComponent(console, c);
    console.setEditable(true); /* set a textarea editable */

    JScrollPane scroll = new JScrollPane(console); /* scrool bar */
    addComponent(scroll, c);
    this.setContentPane(contentPanA);
    

    this.addWindowListener(new WHandler());
    this.pack();
    this.setLocation(200, 100);/*set a position of windows*/
    this.setVisible(true);	
    this.setResizable(true); 
  }

  private void addComponent(JComponent jc, GridBagConstraints gbc) {
    gbl.setConstraints(jc, gbc); /* set a component */
    contentPanA.add(jc); /* add a component*/
  }
}




public class Main {

  public static void main(String[] args) {
	  /**for assume the same aspect as the operating system**/
	  try{
			UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
			}
			catch (Exception e){throw new RuntimeException(e);}
	 
	  Gui l ;
	  l= new Gui();
	 
	  l.setSize(400, 500);

	  
  }

}




import java.awt.event.*;

public class WHandler extends WindowAdapter {

 public void windowClosing(WindowEvent e) {
   System.exit(0);
 }
 
}