NPE in versions:dependency-updates-report

arnaud@mbp-arnaud:~/Projets/Maven/Code/m2-trunks/shared/maven-common-artifact-filters$ mvn versions:dependency-updates-report
[INFO] Scanning for projects...
[INFO] Searching repository for plugin with prefix: 'versions'.
[INFO] ------------------------------------------------------------------------
[INFO] Building Maven Common Artifact Filters
[INFO]    task-segment: [versions:dependency-updates-report]
[INFO] ------------------------------------------------------------------------
[INFO] [versions:dependency-updates-report {execution: default-cli}]
[INFO] artifact easymock:easymock: checking for updates from central
[INFO] artifact junit:junit: checking for updates from central
[INFO] artifact org.apache.maven:maven-artifact: checking for updates from central
[INFO] artifact org.apache.maven:maven-model: checking for updates from central
[INFO] artifact org.apache.maven:maven-plugin-api: checking for updates from central
[INFO] artifact org.apache.maven:maven-project: checking for updates from central
[INFO] artifact org.apache.maven.shared:maven-plugin-testing-harness: checking for updates from central
[INFO] artifact org.apache.maven.shared:maven-test-tools: checking for updates from central
[INFO] artifact org.codehaus.plexus:plexus-container-default: checking for updates from central
[INFO] artifact org.codehaus.plexus:plexus-utils: checking for updates from central
[INFO] ------------------------------------------------------------------------
[ERROR] FATAL ERROR
[INFO] ------------------------------------------------------------------------
[INFO] null
[INFO] ------------------------------------------------------------------------
[INFO] Trace
java.lang.NullPointerException
	at org.codehaus.mojo.versions.ordering.VersionComparators.isSnapshot(VersionComparators.java:147)
	at org.codehaus.mojo.versions.ordering.AbstractVersionComparator.getSegmentCount(AbstractVersionComparator.java:23)
	at org.codehaus.mojo.versions.api.UpdateScope$1.getOldestUpdate(UpdateScope.java:55)
	at org.codehaus.mojo.versions.api.AbstractVersionDetails.getOldestUpdate(AbstractVersionDetails.java:355)
	at org.codehaus.mojo.versions.api.AbstractVersionDetails.getOldestUpdate(AbstractVersionDetails.java:405)
	at org.codehaus.mojo.versions.api.AbstractVersionDetails.getOldestUpdate(AbstractVersionDetails.java:390)
	at org.codehaus.mojo.versions.DependencyUpdatesRenderer.renderSummaryTotalsTable(DependencyUpdatesRenderer.java:125)
	at org.codehaus.mojo.versions.DependencyUpdatesRenderer.renderBody(DependencyUpdatesRenderer.java:70)
	at org.apache.maven.reporting.AbstractMavenReportRenderer.render(AbstractMavenReportRenderer.java:65)
	at org.codehaus.mojo.versions.DependencyUpdatesReport.doGenerateReport(DependencyUpdatesReport.java:87)
	at org.codehaus.mojo.versions.AbstractVersionsReport.executeReport(AbstractVersionsReport.java:248)
	at org.apache.maven.reporting.AbstractMavenReport.generate(AbstractMavenReport.java:90)
	at org.apache.maven.reporting.AbstractMavenReport.execute(AbstractMavenReport.java:65)
	at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:490)
	at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:694)
	at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeStandaloneGoal(DefaultLifecycleExecutor.java:569)
	at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(DefaultLifecycleExecutor.java:539)
	at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHandleFailures(DefaultLifecycleExecutor.java:387)
	at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegments(DefaultLifecycleExecutor.java:348)
	at org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLifecycleExecutor.java:180)
	at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:328)
	at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:138)
	at org.apache.maven.cli.MavenCli.main(MavenCli.java:362)
	at org.apache.maven.cli.compat.CompatibleMain.main(CompatibleMain.java:60)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:585)
	at org.codehaus.classworlds.Launcher.launchEnhanced(Launcher.java:315)
	at org.codehaus.classworlds.Launcher.launch(Launcher.java:255)
	at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:430)
	at org.codehaus.classworlds.Launcher.main(Launcher.java:375)
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 7 seconds
[INFO] Finished at: Wed Aug 12 00:41:22 CEST 2009
[INFO] Final Memory: 15M/27M
[INFO] ------------------------------------------------------------------------