FileChooser Demo dose not work well when AT is enabled

jdk1.6.0-rc b90, snv 43, vermillion 44

steps:
1. enable AT
2. start FileChooser demo
3. click Show FileChooser button
4. click any file on in the FileChooser
5. click Open button to close the File Chooser
6. click Show FileChooser button again

expected result:
The file chooser opens again
actual result:
the file chooser dose not open, and following exceptions in the terminal:
Exception in thread "AWT-EventQueue-1" java.lang.StringIndexOutOfBoundsException
: String index out of range: 20
        at java.lang.String.substring(String.java:1935)
        at org.GNOME.Accessibility.JavaBridge$1.propertyChange(JavaBridge.java:1
72)
        at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSup
port.java:339)
        at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSup
port.java:276)
        at javax.accessibility.AccessibleContext.firePropertyChange(AccessibleCo
ntext.java:726)
        at javax.swing.text.JTextComponent$AccessibleJTextComponent.caretUpdate(
JTextComponent.java:2585)
        at javax.swing.text.JTextComponent.fireCaretUpdate(JTextComponent.java:3
91)
        at javax.swing.text.JTextComponent$MutableCaretEvent.fire(JTextComponent
.java:4389)
        at javax.swing.text.JTextComponent$MutableCaretEvent.stateChanged(JTextC
omponent.java:4411)
        at javax.swing.text.DefaultCaret.fireStateChanged(DefaultCaret.java:782)
        at javax.swing.text.DefaultCaret.changeCaretPosition(DefaultCaret.java:1
257)
        at javax.swing.text.DefaultCaret.handleMoveDot(DefaultCaret.java:1081)
"exception" 59 lines, 4798 characters
        at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:339)
        at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:276)
        at javax.accessibility.AccessibleContext.firePropertyChange(AccessibleContext.java:726)
        at javax.swing.text.JTextComponent$AccessibleJTextComponent.caretUpdate(JTextComponent.java:2585)
        at javax.swing.text.JTextComponent.fireCaretUpdate(JTextComponent.java:391)
        at javax.swing.text.JTextComponent$MutableCaretEvent.fire(JTextComponent.java:4389)
        at javax.swing.text.JTextComponent$MutableCaretEvent.stateChanged(JTextComponent.java:4411)
        at javax.swing.text.DefaultCaret.fireStateChanged(DefaultCaret.java:782) at javax.swing.text.DefaultCaret.changeCaretPosition(DefaultCaret.java:1257)
        at javax.swing.text.DefaultCaret.handleMoveDot(DefaultCaret.java:1081)
        at javax.swing.text.DefaultCaret.moveDot(DefaultCaret.java:1075)
        at javax.swing.text.DefaultCaret.moveDot(DefaultCaret.java:1043)
        at javax.swing.text.JTextComponent.moveCaretPosition(JTextComponent.java:1525)
        at javax.swing.text.JTextComponent.selectAll(JTextComponent.java:1907)
        at javax.swing.plaf.metal.MetalFileChooserUI$5.propertyChange(MetalFileChooserUI.java:765)
        at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:339)
        at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:276)
        at java.awt.Component.firePropertyChange(Component.java:7802)
        at javax.swing.JComponent.addNotify(JComponent.java:4646)
        at java.awt.Container.addNotify(Container.java:2518)
        at javax.swing.JComponent.addNotify(JComponent.java:4645)
        at java.awt.Container.addNotify(Container.java:2518)
        at javax.swing.JComponent.addNotify(JComponent.java:4645)
        at java.awt.Container.addNotify(Container.java:2518)
        at javax.swing.JComponent.addNotify(JComponent.java:4645)
        at javax.swing.JRootPane.addNotify(JRootPane.java:730)
        at java.awt.Container.addNotify(Container.java:2518)
        at java.awt.Window.addNotify(Window.java:633)
        at java.awt.Dialog.addNotify(Dialog.java:744)
        at java.awt.Window.pack(Window.java:661)
        at javax.swing.JFileChooser.createDialog(JFileChooser.java:774)
        at javax.swing.JFileChooser.showDialog(JFileChooser.java:709)
        at FileChooserDemo.actionPerformed(FileChooserDemo.java:394)
        at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
        at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)
        at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
        at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
        at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
        at java.awt.Component.processMouseEvent(Component.java:5999)
        at javax.swing.JComponent.processMouseEvent(JComponent.java:3240)
        at java.awt.Component.processEvent(Component.java:5764)
        at java.awt.Container.processEvent(Container.java:1984)
        at java.awt.Component.dispatchEventImpl(Component.java:4407)
        at java.awt.Container.dispatchEventImpl(Container.java:2042)
        at java.awt.Component.dispatchEvent(Component.java:4237)
        at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4248)
        at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3912) at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3842)
        at java.awt.Container.dispatchEventImpl(Container.java:2028)