com.atlassian.clover.api.CloverException: java.lang.IllegalArgumentException: Comparison method violates its general contract!
	at com.cenqua.clover.reporters.html.HtmlReporter.executeImpl(HtmlReporter.java:165)
	at com.cenqua.clover.reporters.CloverReporter.execute(CloverReporter.java:41)
	at com.cenqua.clover.tasks.CloverReportTask.generateReports(CloverReportTask.java:427)
	at com.cenqua.clover.tasks.CloverReportTask.cloverExecute(CloverReportTask.java:384)
	at com.cenqua.clover.tasks.AbstractCloverTask.execute(AbstractCloverTask.java:55)
	at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:291)
	at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:606)
	at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
	at org.apache.tools.ant.Task.perform(Task.java:348)
	at org.apache.tools.ant.Target.execute(Target.java:390)
	at org.apache.tools.ant.Target.performTasks(Target.java:411)
	at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1399)
	at org.apache.tools.ant.helper.SingleCheckExecutor.executeTargets(SingleCheckExecutor.java:38)
	at org.apache.tools.ant.Project.executeTargets(Project.java:1251)
	at org.apache.tools.ant.taskdefs.Ant.execute(Ant.java:442)
	at org.apache.tools.ant.taskdefs.SubAnt.execute(SubAnt.java:302)
	at org.apache.tools.ant.taskdefs.SubAnt.execute(SubAnt.java:221)
	at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:291)
	at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:606)
	at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
	at org.apache.tools.ant.Task.perform(Task.java:348)
	at org.apache.tools.ant.Target.execute(Target.java:390)
	at org.apache.tools.ant.Target.performTasks(Target.java:411)
	at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1399)
	at org.apache.tools.ant.helper.SingleCheckExecutor.executeTargets(SingleCheckExecutor.java:38)
	at org.apache.tools.ant.Project.executeTargets(Project.java:1251)
	at org.apache.tools.ant.taskdefs.Ant.execute(Ant.java:442)
	at org.apache.tools.ant.taskdefs.CallTarget.execute(CallTarget.java:105)
	at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:291)
	at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:606)
	at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
	at org.apache.tools.ant.Task.perform(Task.java:348)
	at org.apache.tools.ant.Target.execute(Target.java:390)
	at org.apache.tools.ant.Target.performTasks(Target.java:411)
	at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1399)
	at org.apache.tools.ant.helper.SingleCheckExecutor.executeTargets(SingleCheckExecutor.java:38)
	at org.apache.tools.ant.Project.executeTargets(Project.java:1251)
	at org.apache.tools.ant.taskdefs.Ant.execute(Ant.java:442)
	at org.apache.tools.ant.taskdefs.CallTarget.execute(CallTarget.java:105)
	at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:291)
	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:606)
	at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
	at org.apache.tools.ant.Task.perform(Task.java:348)
	at org.apache.tools.ant.Target.execute(Target.java:390)
	at org.apache.tools.ant.Target.performTasks(Target.java:411)
	at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1399)
	at org.apache.tools.ant.Project.executeTarget(Project.java:1368)
	at org.apache.tools.ant.helper.DefaultExecutor.executeTargets(DefaultExecutor.java:41)
	at org.apache.tools.ant.Project.executeTargets(Project.java:1251)
	at org.apache.tools.ant.Main.runBuild(Main.java:809)
	at org.apache.tools.ant.Main.startAnt(Main.java:217)
	at org.apache.tools.ant.launch.Launcher.run(Launcher.java:280)
	at org.apache.tools.ant.launch.Launcher.main(Launcher.java:109)
Caused by: java.lang.IllegalArgumentException: Comparison method violates its general contract!
	at java.util.TimSort.mergeLo(TimSort.java:747)
	at java.util.TimSort.mergeAt(TimSort.java:483)
	at java.util.TimSort.mergeForceCollapse(TimSort.java:426)
	at java.util.TimSort.sort(TimSort.java:223)
	at java.util.TimSort.sort(TimSort.java:173)
	at java.util.Arrays.sort(Arrays.java:659)
	at java.util.Collections.sort(Collections.java:217)
	at com.cenqua.clover.reporters.html.RenderTestResultAction.call(RenderTestResultAction.java:93)
	at com.cenqua.clover.util.CloverExecutors$CloverExecutorService.submit(CloverExecutors.java:70)
	at com.cenqua.clover.reporters.html.HtmlReporter.renderTestPages(HtmlReporter.java:719)
	at com.cenqua.clover.reporters.html.HtmlReporter.processPackage(HtmlReporter.java:665)
	at com.cenqua.clover.reporters.html.HtmlReporter.executeCurrentReport(HtmlReporter.java:228)
	at com.cenqua.clover.reporters.html.HtmlReporter.executeImpl(HtmlReporter.java:157)
	... 61 more