Unexpected exception while fixing a problem

[naoliv]

What steps will reproduce the problem?

1. Clicked on validate to search for problems
2. Found a "No tags - Unconnected nodes without physical tags"
3. Selected (on the map area) the node and deleted it
4. Clicked on the problem (in the validation area) and clicked "Fix"
5. Got a "An unexpected exception ocurred"

What is the expected result?

JOSM should somehow verify that the node is already deleted and do nothing when clicking on "Fix"

What happens instead?

Gets an exception.

Please provide any additional information below. Attach a screenshot if
possible.

Debian-Release: 0.0.svn4064-2
Build-Date: 2011-05-03 17:18:13
Revision: 4064
Is-Local-Build: true

Identification: JOSM/1.5 (4064 pt_BR)
Memory Usage: 299 MB / 881 MB (181 MB allocated, but free)
Java version: 1.6.0_25, Sun Microsystems Inc., Java HotSpot(TM) 64-Bit Server VM
Operating system: Linux
Dataset consistency test: No problems found

Plugin: ImproveWayAccuracy (26025)
Plugin: buildings_tools (25905)

java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
	at org.openstreetmap.josm.gui.dialogs.ValidatorDialog$FixTask.realRun(ValidatorDialog.java:582)
	at org.openstreetmap.josm.gui.PleaseWaitRunnable.doRealRun(PleaseWaitRunnable.java:83)
	at org.openstreetmap.josm.gui.PleaseWaitRunnable.run(PleaseWaitRunnable.java:129)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
	at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
	at java.util.concurrent.FutureTask.run(FutureTask.java:138)
	at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
	at java.lang.Thread.run(Thread.java:662)
Caused by: java.lang.reflect.InvocationTargetException
	at java.awt.EventQueue.invokeAndWait(EventQueue.java:1042)
	at javax.swing.SwingUtilities.invokeAndWait(SwingUtilities.java:1326)
	at org.openstreetmap.josm.gui.dialogs.ValidatorDialog$FixTask.realRun(ValidatorDialog.java:557)
	... 8 more
Caused by: java.lang.IllegalArgumentException: {Node id=1316078511 version=1 MVD lat=-21.178803709315098,lon=-50.46568858736658} is already deleted
	at org.openstreetmap.josm.command.DeleteCommand.executeCommand(DeleteCommand.java:117)
	at org.openstreetmap.josm.command.SequenceCommand.executeCommand(SequenceCommand.java:53)
	at org.openstreetmap.josm.data.UndoRedoHandler.addNoRedraw(UndoRedoHandler.java:36)
	at org.openstreetmap.josm.gui.dialogs.ValidatorDialog$FixTask$1.run(ValidatorDialog.java:560)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:199)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:641)
	at java.awt.EventQueue.access$000(EventQueue.java:84)
	at java.awt.EventQueue$1.run(EventQueue.java:602)
	at java.awt.EventQueue$1.run(EventQueue.java:600)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:611)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:178)
	at java.awt.Dialog$1.run(Dialog.java:1046)
	at java.awt.Dialog$3.run(Dialog.java:1098)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.awt.Dialog.show(Dialog.java:1096)
	at java.awt.Component.show(Component.java:1584)
	at java.awt.Component.setVisible(Component.java:1536)
	at java.awt.Window.setVisible(Window.java:842)
	at java.awt.Dialog.setVisible(Dialog.java:986)
	at org.openstreetmap.josm.gui.progress.PleaseWaitProgressMonitor$3.run(PleaseWaitProgressMonitor.java:83)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:641)
	at java.awt.EventQueue.access$000(EventQueue.java:84)
	at java.awt.EventQueue$1.run(EventQueue.java:602)
	at java.awt.EventQueue$1.run(EventQueue.java:600)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:611)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:12