Join Buildings JOSM error

[andrew.finney@…]

What steps will reproduce the problem?

1. Select two slightly overlapping shapes assigned as buildings, one with a relationship to the road it is situated in, adding each using the CTRL key.
2. Press shift+j
3. Check data on the relationship window is correct and click o.k. to apply the data from the relationship to the combined shape/building.

What is the expected result?
The overlapped shapes become one single combined unit with the relationship applied.

What happens instead?
You have encountered a bug in JOSM screen.

Repository Root: ​http://josm.openstreetmap.de/svn
Build-Date: 2010-12-31 02:31:28
Last Changed Author: bastiK
Revision: 3751
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
URL: ​http://josm.openstreetmap.de/svn/trunk
Last Changed Date: 2010-12-30 16:31:05 +0100 (Thu, 30 Dec 2010)
Last Changed Rev: 3751

Identification: JOSM/1.5 (3751 en)
Memory Usage: 132 MB / 247 MB (35 MB allocated, but free)
Java version: 1.6.0_23, Sun Microsystems Inc., Java HotSpot(TM) Client VM
Operating system: Windows XP
Dataset consistency test: No problems found

Plugin: PicLayer (24308)
Plugin: buildings_tools (23804)
Plugin: terracer (24956)

java.lang.RuntimeException: Join areas internal error.

at org.openstreetmap.josm.actions.JoinAreasAction.findBoundaryPolygons(JoinAreasAction.java:1047)
at org.openstreetmap.josm.actions.JoinAreasAction.joinAreas(JoinAreasAction.java:477)
at org.openstreetmap.josm.actions.JoinAreasAction.actionPerformed(JoinAreasAction.java:371)
at javax.swing.SwingUtilities.notifyAction(Unknown Source)
at javax.swing.JComponent.processKeyBinding(Unknown Source)
at javax.swing.KeyboardManager.fireBinding(Unknown Source)
at javax.swing.KeyboardManager.fireKeyboardAction(Unknown Source)
at javax.swing.JComponent.processKeyBindingsForAllComponents(Unknown Source)
at javax.swing.JComponent.processKeyBindings(Unknown Source)
at javax.swing.JComponent.processKeyEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.KeyboardFocusManager.redispatchEvent(Unknown Source)
at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(Unknown Source)
at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(Unknown Source)
at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(Unknown Source)
at java.awt.DefaultKeyboardFocusManager.dispatchEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(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)

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

Repository Root: http://josm.openstreetmap.de/svn
Build-Date: 2010-12-31 02:31:28
Last Changed Author: bastiK
Revision: 3751
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
URL: http://josm.openstreetmap.de/svn/trunk
Last Changed Date: 2010-12-30 16:31:05 +0100 (Thu, 30 Dec 2010)
Last Changed Rev: 3751

Identification: JOSM/1.5 (3751 en)
Memory Usage: 132 MB / 247 MB (35 MB allocated, but free)
Java version: 1.6.0_23, Sun Microsystems Inc., Java HotSpot(TM) Client VM
Operating system: Windows XP
Dataset consistency test: No problems found

Plugin: PicLayer (24308)
Plugin: buildings_tools (23804)
Plugin: terracer (24956)

java.lang.RuntimeException: Join areas internal error.
	at org.openstreetmap.josm.actions.JoinAreasAction.findBoundaryPolygons(JoinAreasAction.java:1047)
	at org.openstreetmap.josm.actions.JoinAreasAction.joinAreas(JoinAreasAction.java:477)
	at org.openstreetmap.josm.actions.JoinAreasAction.actionPerformed(JoinAreasAction.java:371)
	at javax.swing.SwingUtilities.notifyAction(Unknown Source)
	at javax.swing.JComponent.processKeyBinding%2