codice:
class pannello1 extends JPanel implements MouseMotionListener {
   public void paintComponent(Graphics g){
   super.paintComponent(g);
   g.setFont(Arial_font_plain_14);
   g.setColor(Color.black);
   g.drawString(s1,10,20);
   g.drawString(s2,10,35);
   g.setColor(Color.blue);
   g.drawString(s3,10,50);
   g.setColor(Color.red);
   g.drawString(s4,10,65);
   g.setColor(Color.green);
   g.drawString(s5,10,80);
   setBackground(Color.white);
   tk=Toolkit.getDefaultToolkit();
   img=tk.getImage("checks.gif");
   img1=tk.getImage("Mappa_arena.gif");
   tracker=new MediaTracker(this);
   tracker.addImage(img,0);
   tracker.addImage(img1,1);
   try {
	tracker.waitForAll();
   }
   catch (InterruptedException e) {
    System.out.println("Errore, impossibile caricare le immagini");
    JOptionPane.showMessageDialog (null, "Impossibile caricare le immagini", "Errore", JOptionPane.ERROR_MESSAGE);
   }
   g.drawImage(img,323,0,this);
   g.drawImage(img1,0,100,this);	

   addMouseListener(new MouseAdapter() {
    	public void mousePressed(MouseEvent e) {}		
    				
        public void mouseClicked(MouseEvent e) { 
	     int x=e.getX();
     	     int y=e.getY(); //
	     if (trova(x,y)>=1 && (e.getClickCount() >= 2) ) {
		ordina = new OrdinaPosti();
		ordina.show(); 
	     } 
        }
   });
   addMouseMotionListener(this);
  }

  public void mouseDragged(MouseEvent e){ }
  public void mouseMoved(MouseEvent e) {
   int x = e.getX();
   int y = e.getY();
   if (trova(x, y) >= 0)
    setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
    else
    setCursor(Cursor.getDefaultCursor());
   }				
 }
in pratica ho aggiunto il mouselistener al pannello