Corrupted Java development environment

Well, it happened again.

My WDSC 6.0.1 install was working fine ... then, all of a sudden, I
can't debug java code anymore.

When I hover over a variable in the debugger, it just displays the
object definition.  This often happens if the "add debug info to
classes" setting is off.

When I try change the java project settings, I get a "The currently
displayed page contains invalid values".

When I go into the Java/Compiler preferences, I get the same error.

My .log file contains a NullPointerException error & stack trace (at the
bottom of this message).

Any ideas on how I can solve this problem?   I *REALLY* don't want to
have to recreate my projects again.

david

!ENTRY org.eclipse.core.runtime 4 2 Jan 24, 2007 11:55:03.738
!MESSAGE Problems occurred when invoking code from plug-in:
"org.eclipse.core.runtime".
!STACK 0
java.lang.NullPointerException
        at
org.eclipse.jdt.internal.ui.preferences.CompilerConfigurationBlock.validateMaxNumberProblems(Unknown
Source)
        at
org.eclipse.jdt.internal.ui.preferences.CompilerConfigurationBlock.validateSettings(Unknown
Source)
        at
org.eclipse.jdt.internal.ui.preferences.CompilerConfigurationBlock.createContents(Unknown
Source)
        at
org.eclipse.jdt.internal.ui.preferences.CompilerPropertyPage.createContents(Unknown
Source)
        at org.eclipse.jface.preference.PreferencePage.createControl(Unknown
Source)
        at
org.eclipse.jdt.internal.ui.preferences.CompilerPropertyPage.createControl(Unknown
Source)
        at org.eclipse.jface.preference.PreferenceDialog$12.run(Unknown Source)
        at org.eclipse.core.internal.runtime.InternalPlatform.run(Unknown 
Source)
        at org.eclipse.core.runtime.Platform.run(Unknown Source)
        at org.eclipse.jface.preference.PreferenceDialog.showPage(Unknown 
Source)
        at
org.eclipse.jface.preference.PreferenceDialog$8.selectionChanged(Unknown
Source)
        at org.eclipse.jface.viewers.StructuredViewer$3.run(Unknown Source)
        at org.eclipse.core.internal.runtime.InternalPlatform.run(Unknown 
Source)
        at org.eclipse.core.runtime.Platform.run(Unknown Source)
        at
org.eclipse.jface.viewers.StructuredViewer.firePostSelectionChanged(Unknown
Source)
        at org.eclipse.jface.viewers.StructuredViewer.handlePostSelect(Unknown
Source)
        at org.eclipse.jface.viewers.StructuredViewer$5.widgetSelected(Unknown
Source)
        at org.eclipse.jface.util.OpenStrategy.firePostSelectionEvent(Unknown
Source)
        at org.eclipse.jface.util.OpenStrategy.access$4(Unknown Source)
        at org.eclipse.jface.util.OpenStrategy$3.run(Unknown Source)
        at org.eclipse.swt.widgets.RunnableLock.run(Unknown Source)
        at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Unknown Source)
        at org.eclipse.swt.widgets.Display.runAsyncMessages(Unknown Source)
        at org.eclipse.swt.widgets.Display.readAndDispatch(Unknown Source)
        at org.eclipse.jface.window.Window.runEventLoop(Unknown Source)
        at org.eclipse.jface.window.Window.open(Unknown Source)
        at org.eclipse.ui.dialogs.PropertyDialogAction.run(Unknown Source)
        at org.eclipse.jface.action.Action.runWithEvent(Unknown Source)
        at
org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(Unknown
Source)
        at org.eclipse.jface.action.ActionContributionItem.access$2(Unknown 
Source)
        at
org.eclipse.jface.action.ActionContributionItem$7.handleEvent(Unknown
Source)
        at org.eclipse.swt.widgets.EventTable.sendEvent(Unknown Source)
        at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
        at org.eclipse.swt.widgets.Display.runDeferredEvents(Unknown Source)
        at org.eclipse.swt.widgets.Display.readAndDispatch(Unknown Source)
        at org.eclipse.ui.internal.Workbench.runEventLoop(Unknown Source)
        at org.eclipse.ui.internal.Workbench.runUI(Unknown Source)
        at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Unknown 
Source)
        at org.eclipse.ui.PlatformUI.createAndRunWorkbench(Unknown Source)
        at org.eclipse.ui.internal.ide.IDEApplication.run(Unknown Source)
        at org.eclipse.core.internal.runtime.PlatformActivator$1.run(Unknown
Source)
        at
org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:273)
        at
org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:129)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:85)
        at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:58)
        at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:60)
        at java.lang.reflect.Method.invoke(Method.java:391)
        at org.eclipse.core.launcher.Main.basicRun(Main.java:185)
        at org.eclipse.core.launcher.Main.run(Main.java:704)
        at org.eclipse.core.launcher.Main.main(Main.java:688)