Helma Debugger Error in 1.6.0 rc1

There appears to be an error in the Javascript Helma/Rhino Debugger.
When a breakpoint is hit in the javascript debugger, the following trace
is created below and the "Locals" variable tab is empty.  The "this" tab
contains the functions but no variable entries.  I have tried to find the
issue and have not been able to.

-Kris

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
        at 
org.mozilla.javascript.tools.debugger.VariableModel.children(SwingGui
.java:2651)
        at 
org.mozilla.javascript.tools.debugger.VariableModel.isLeaf(SwingGui.j
ava:2541)
        at 
javax.swing.plaf.basic.BasicTreeUI$NodeDimensionsHandler.getNodeDimen
sions(Unknown Source)
        at 
javax.swing.tree.AbstractLayoutCache.getNodeDimensions(Unknown Source
)
        at 
javax.swing.tree.VariableHeightLayoutCache$TreeStateNode.updatePrefer
redSize(Unknown Source)
        at 
javax.swing.tree.VariableHeightLayoutCache$TreeStateNode.expand(Unkno
wn Source)
        at 
javax.swing.tree.VariableHeightLayoutCache$TreeStateNode.expand(Unkno
wn Source)
        at javax.swing.tree.VariableHeightLayoutCache.rebuild(Unknown 
Source)
        at javax.swing.tree.VariableHeightLayoutCache.setModel(Unknown 
Source)
        at javax.swing.plaf.basic.BasicTreeUI.setModel(Unknown Source)
        at 
javax.swing.plaf.basic.BasicTreeUI$Handler.propertyChange(Unknown Sou
rce)
        at java.beans.PropertyChangeSupport.firePropertyChange(Unknown 
Source)
        at java.beans.PropertyChangeSupport.firePropertyChange(Unknown 
Source)
        at java.awt.Component.firePropertyChange(Unknown Source)
        at javax.swing.JTree.setModel(Unknown Source)
        at javax.swing.JTree.<init>(Unknown Source)
        at 
org.mozilla.javascript.tools.debugger.downloaded.JTreeTable$TreeTable
CellRenderer.<init>(JTreeTable.java:132)
        at 
org.mozilla.javascript.tools.debugger.MyTreeTable.resetTree(SwingGui.
java:2752)
        at 
org.mozilla.javascript.tools.debugger.ContextWindow.actionPerformed(S
wingGui.java:3191)
        at javax.swing.JComboBox.fireActionEvent(Unknown Source)
        at javax.swing.JComboBox.setSelectedItem(Unknown Source)
        at javax.swing.JComboBox.setSelectedIndex(Unknown Source)
        at 
org.mozilla.javascript.tools.debugger.SwingGui.enterInterruptImpl(Swi
ngGui.java:625)
        at 
org.mozilla.javascript.tools.debugger.RunProxy.run(SwingGui.java:3576
)
        at java.awt.event.InvocationEvent.dispatch(Unknown Source)
        at java.awt.EventQueue.dispatchEvent(Unknown Source)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown 
Source)
        at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown 
Source)
        at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
        at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
        at java.awt.EventDispatchThread.run(Unknown Source)