Why does AffineTransform not work on JTextPane?

I can rotate every other type of component I've tried, but when I
rotate a JTextPane by 90 or 180 degrees (which I REALLY need for my
customer's application) The clipping and bordering get all messed up
and I'm at my wit's end trying to make it work.

Am I doing something wrong, or is there a Java bug in applying a
transform to a JTextPane? The same basic code works on a JLabel, why
won't it work on a JTextPane?

Any ideas or suggestions would be deeply appreciated.

OR any ideas for a different way to display STYLED text (font, size,
color, bold, italic on a character-by-character basis) at a 90 or 180
degree rotation. It doesn't have to be editable when rotated, but it
does need to be editable when upright, otherwise I'd just use HTML in a
JLabel.

Thanks,

--gary

Compilable example:

import javax.swing.*;
import javax.swing.text.*;
import javax.swing.border.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.awt.image.*;

public class Rotate extends JPanel {

    private TextPanel textPane;
    private JLayeredPane parent;

    public Rotate() {

        setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
        JToolBar toolBar = buildToolbar();
        add(toolBar);

        parent = new JLayeredPane();
        add(parent);
        parent.setBackground( Color.gray);
        parent.setPreferredSize(new Dimension(640, 480));

        // Create a text pane.

        textPane = new TextPanel();
        StyledDocument doc = textPane.getStyledDocument();
        try {
            doc.insertString(doc.getLength(), "This is some sample
text.\nIt can be Rotated.", null);
        }
        catch (BadLocationException ble) {
            System.err.println("Couldn't insert initial text into text
pane.");
        }
        Border myBorder = BorderFactory.createLineBorder( Color.red );
        textPane.setBorder(myBorder);
        parent.setOpaque(true);
        parent.add(textPane);
        textPane.setDefaultBounds(120, 120, 240, 120);
    }
    private JToolBar buildToolbar() {

        JToolBar toolBar = new JToolBar();
        toolBar.setRollover( true );
        toolBar.setFloatable( false );
        JButton rotateButton = new JButton("Rotate");
        rotateButton.setToolTipText( "Rotate text editing pane" );
        rotateButton.addActionListener( new ActionListener() {
            public void actionPerformed( ActionEvent e ) {
                textPane.setRotation(textPane.getRotation()+1);
            }
        });
        toolBar.add( rotateButton );
        return toolBar;
    }
    private static void createAndShowGUI() {
        //Make sure we have nice window decorations.
        JFrame.setDefaultLookAndFeelDecorated(true);

        //Create and set up the window.
        JFrame frame = new JFrame("Rotate");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Create and set up the content pane.
        JComponent newContentPane = new Rotate();
        newContentPane.setOpaque(true); //content panes must be opaque
        frame.setContentPane(newContentPane);

        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        //Schedule a job for the event-dispatching thread:
        //creating and showing this application's GUI.
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }

}

class TextPanel extends JTextPane {

    // implements rotation for a JTextPane

    private int rotation;
    private int tx, ty;
    private int wide, high;

    // valid rotation values are:
    // 0 = no rotation
    // 1 = rotation 90 degree clockwise
    // 2 = rotation 180 degrees
    // 3 = rotation 90 degrees counterclockwise

    TextPanel() {
        super();
        rotation = 0;
        tx = 0;
        ty = 0;
    }
    public void setDefaultBounds( int x, int y, int width, int height)
{
        high = height;
        wide = width;
        super.setBounds(x,y,width,height);
    }
    public void setRotation( int newRotation ) {
        rotation = newRotation % 4;

        if ((rotation%2)==0) {
            setSize(wide,high);
        } else {
            setSize(high,wide);
        }
        switch (rotation) {
            case 0 : tx = 0; ty = 0; break;
            case 1 : tx = 1; ty = 0; break;
            case 2 : tx = 1; ty = 1; break;
            case 3 : tx = 0; ty = 1; break;
        }
        repaint();
    }
    public int getRotation() { return rotation; }

    public void paintComponent(Graphics g) {

        Graphics2D g2 = (Graphics2D) g;
        double angle = rotation * Math.PI/2;
        AffineTransform tr = g2.getTransform();
        int h,w;
        if ((rotation%2) == 0) {
            w = wide;
            h = high;
        } else {
            h = wide;
            w = high;
        }

        tr.setToTranslation(getWidth()*tx,getHeight()*ty);
        tr.rotate(angle);
        g2.setTransform(tr); // <----- comment this line out to see
correct borders
        super.paintComponent(g2);
    }
}