Bug in JTextArea/JTextPane ??

Hi,
I am facing huge memory leak problems with JTextArea/JTextPane. After considerable investigation, I found out that the Document associated with the component is not being GC'ed properly. I ran OptimizeIt and found out that the memory is being consumed by the JTextPane.setText() method. I have implmented a HTML viewer to display large amounts of HTML data and it is leaking memory like crazy on each successive execution. Any thoughts ??
JDK1.4.2_01, WinXP
Here is the code fragment:
public class ReportViewer extends BaseFrame implements FontChange_int
     private     String          cReport;
     private boolean          testMode = false;
     // Graphical components
     private     BorderLayout     cMainLayout;
     private     JButton          cClose;
     private     JTextPane     cRptPane;
     private     Button          cClose2;
     private ViewUpdater cViewUpdater = null;
     // Constants
     final     static     int     startupXSize = 650;
     final     static     int     startupYSize = 500;
     // Methods
     public ReportViewer(String report, ReportMain main)
          // BaseFrame extends JFrame
          super("Reports Viewer", true, startupXSize, startupYSize);
          testMode = false;
          cReport = report;
          cViewUpdater = new ViewUpdater();
          initialize();
     public void initialize()
          // Create main layout manager
          cMainLayout = new BorderLayout();
          getContentPane().setLayout(cMainLayout);
          // Quick button bar - print, export, save as
          JToolBar     topPanel = new JToolBar();
          topPanel.setBorder(new BevelBorder(BevelBorder.RAISED) );
          java.net.URL     url;
          topPanel.add(Box.createHorizontalStrut(10));
          url = Scm.class.getResource("images/Exit.gif");
          cClose = new Button(new ImageIcon(url), true);
          cClose.setToolTipText("Close Window");
          topPanel.add(cClose);
          getContentPane().add(topPanel, BorderLayout.NORTH);
          // Main view window - HTML
          cRptPane = new JTextPane();
          cRptPane.setContentType("text/html");
          cRptPane.setEditable(false);
          JScrollPane sp = new JScrollPane(cRptPane);
          getContentPane().add(sp, BorderLayout.CENTER);
          // Main button - Close
          JPanel     bottomPanel = new JPanel();
          url = Scm.class.getResource("images/Exit.gif");
          cClose2 = new Button(new ImageIcon(url), "Close");
          bottomPanel.add(cClose2);
          getContentPane().add(bottomPanel, BorderLayout.SOUTH);
          cClose.addActionListener(new ActionListener() {
               public void actionPerformed(ActionEvent e) {
                    closeWindow();
          cClose2.addActionListener(new ActionListener() {
               public void actionPerformed(ActionEvent e) {
                    closeWindow();
          show();
          cViewUpdater.setText(cReport);
          SwingUtilities.invokeLater(cViewUpdater);
     protected void
     closeWindow()
          super.closeWindow();
          // If I add the following lines, the GC reclaims
// part of the memory but does not flush out the text
// component as a whole
          /*Document doc = cRptPane.getDocument();
          try
               doc.remove(0,doc.getLength());
          catch(Exception e) {;}
          doc=null; */
          cRptPane=null;
          cReport = null;
          cViewUpdater = null;
          dispose();
     private class ViewUpdater implements Runnable
          private String cText = null;
          public ViewUpdater() {;}
          public void
          setText(String text) {
               cText = text;
          public void
          run() {
               cRptPane.setText(cText);
               cRptPane.setCaretPosition(0);
               cText = null;
     // Local main - for testing
     public static void main(String args[])
          //new ReportViewer(str,comp);
Sudarshan
www.spectrumscm.com

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