exception raised when click on scrollbar down arrow repeatedly.

java version "1.3"
Classic VM (build JDK-1.3-J, green threads, sunwjit)
SunOS tuna 5.7 Generic sun4u sparc SUNW,Ultra-5_10

to reproduce, compile and run the attatched program.

tuna:/space/test/bug/JTable 203 % java TableDemo
Exception occurred during event dispatching:
java.lang.ArrayIndexOutOfBoundsException: -1
        at TableDemo$MyTableModel.getValueAt(TableDemo.java, Compiled Code)
        at javax.swing.JTable.getValueAt(JTable.java, Compiled Code)
        at javax.swing.JTable.prepareRenderer(JTable.java, Compiled Code)
        at javax.swing.plaf.basic.BasicTableUI.paintCell(BasicTableUI.java, Compiled Code)
        at javax.swing.plaf.basic.BasicTableUI.paintCells(BasicTableUI.java, Compiled Code)
        at javax.swing.plaf.basic.BasicTableUI.paint(BasicTableUI.java, Compiled Code)
        at javax.swing.plaf.ComponentUI.update(ComponentUI.java, Compiled Code)
        at javax.swing.JComponent.paintComponent(JComponent.java, Compiled Code)
        at javax.swing.JComponent.paint(JComponent.java, Compiled Code)
        at javax.swing.JViewport.windowBlitPaint(JViewport.java, Compiled Code)
        at javax.swing.JViewport.setViewPosition(JViewport.java, Compiled Code)
        at javax.swing.plaf.basic.BasicScrollPaneUI$VSBChangeListener.stateChanged(BasicScrollPaneUI.java, Compiled Code)
        at javax.swing.DefaultBoundedRangeModel.fireStateChanged(DefaultBoundedRangeModel.java, Compiled Code)
        at javax.swing.DefaultBoundedRangeModel.setRangeProperties(DefaultBoundedRangeModel.java, Compiled Code)
        at javax.swing.DefaultBoundedRangeModel.setValue(DefaultBoundedRangeModel.java, Compiled Code)
        at javax.swing.JScrollBar.setValue(JScrollBar.java, Compiled Code)
        at javax.swing.plaf.basic.BasicScrollBarUI.scrollByUnit(BasicScrollBarUI.java, Compiled Code)
        at javax.swing.plaf.basic.BasicScrollBarUI$ArrowButtonListener.mousePressed(BasicScrollBarUI.java, Compiled Code)
        at java.awt.AWTEventMulticaster.mousePressed(AWTEventMulticaster.java, Compiled Code)
        at java.awt.Component.processMouseEvent(Component.java, Compiled Code)
        at java.awt.Component.processEvent(Component.java, Compiled Code)
        at java.awt.Container.processEvent(Container.java, Compiled Code)
        at java.awt.Component.dispatchEventImpl(Component.java, Compiled Code)
        at java.awt.Container.dispatchEventImpl(Container.java, Compiled Code)
        at java.awt.Component.dispatchEvent(Component.java, Compiled Code)
        at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java, Compiled Code)
        at java.awt.LightweightDispatcher.processMouseEvent(Container.java, Compiled Code)
        at java.awt.LightweightDispatcher.dispatchEvent(Container.java, Compiled Code)
        at java.awt.Container.dispatchEventImpl(Container.java, Compiled Code)
        at java.awt.Window.dispatchEventImpl(Window.java, Compiled Code)
        at java.awt.Component.dispatchEvent(Component.java, Compiled Code)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java, Compiled Code)
        at java.awt.EventDispatchThread.pumpOneEvent(EventDispatchThread.java, Compiled Code)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java, Compiled Code)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java, Compiled Code)