LiveGPS plugin fails at startup

[james@…]

What steps will reproduce the problem?

1. open any OSM file

What is the expected result?
No error.

What happens instead?
The following error message appears. I've never been able to use the livegps plugin so I don't know anything about expected behavior.

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

Repository Root: http://josm.openstreetmap.de/svn
Build-Date: 2012-07-03 01:31:22
Last Changed Author: simon04
Revision: 5315
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
URL: http://josm.openstreetmap.de/svn/trunk
Last Changed Date: 2012-07-02 14:51:19 +0200 (Mon, 02 Jul 2012)
Last Changed Rev: 5315

Identification: JOSM/1.5 (5315 en)
Memory Usage: 207 MB / 1728 MB (84 MB allocated, but free)
Java version: 1.6.0_24, Sun Microsystems Inc., OpenJDK 64-Bit Server VM
Operating system: Linux
Dataset consistency test: No problems found

Plugin: ImageWayPoint (27852)
Plugin: buildings_tools (28412)
Plugin: dataimport (28412)
Plugin: download_along (28412)
Plugin: editgpx (27679)
Plugin: gpxfilter (28412)
Plugin: importvec (28412)
Plugin: livegps (27679)
Plugin: mapdust (28412)
Plugin: measurement (27679)
Plugin: merge-overlap (28412)
Plugin: openstreetbugs (28412)
Plugin: osmarender (28412)
Plugin: pdfimport (28448)
Plugin: photo_geotagging (28412)
Plugin: print (28412)
Plugin: proj4j (28412)
Plugin: reverter (28412)

org.openstreetmap.josm.plugins.PluginException: An error occurred in plugin livegps
	at org.openstreetmap.josm.plugins.PluginProxy.mapFrameInitialized(PluginProxy.java:32)
	at org.openstreetmap.josm.plugins.PluginHandler.notifyMapFrameChanged(PluginHandler.java:858)
	at org.openstreetmap.josm.Main.setMapFrame(Main.java:211)
	at org.openstreetmap.josm.Main.addLayer(Main.java:365)
	at org.openstreetmap.josm.io.OsmImporter$1.run(OsmImporter.java:75)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:226)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:647)
	at java.awt.EventQueue.access$000(EventQueue.java:96)
	at java.awt.EventQueue$1.run(EventQueue.java:608)
	at java.awt.EventQueue$1.run(EventQueue.java:606)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:105)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:617)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:275)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:200)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:194)
	at java.awt.Dialog$1.run(Dialog.java:1072)
	at java.awt.Dialog$3.run(Dialog.java:1126)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.awt.Dialog.show(Dialog.java:1124)
	at java.awt.Component.show(Component.java:1551)
	at java.awt.Component.setVisible(Component.java:1503)
	at java.awt.Window.setVisible(Window.java:881)
	at java.awt.Dialog.setVisible(Dialog.java:1011)
	at org.openstreetmap.josm.gui.progress.PleaseWaitProgressMonitor$4.run(PleaseWaitProgressMonitor.java:170)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:226)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:647)
	at java.awt.EventQueue.access$000(EventQueue.java:96)
	at java.awt.EventQueue$1.run(EventQueue.java:608)
	at java.awt.EventQueue$1.run(EventQueue.java:606)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:105)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:617)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:275)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:200)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:190)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:185)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:177)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:138)
Caused by: java.lang.reflect.InvocationTargetException
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:616)
	at org.openstreetmap.josm.plugins.PluginProxy.mapFrameInitialized(PluginProxy.java:29)
	... 38 more
Caused by: java.lang.NoSuchMethodError: org.openstreetmap.josm.tools.Shortcut.registerShortcut(Ljava/lang/String;Ljava/lang/String;III)Lorg/openstreetmap/josm/tools/Shortcut;
	at livegps.LiveGpsDialog.<init>(LiveGpsDialog.java:45)
	at livegps.LiveGpsPlugin.mapFrameInitialized(LiveGpsPlugin.java:225)
	... 43 mo