Occasionally, when gathering code coverage results via Hudson using the Emma Plug-In, an java.lang.NullPointerException is thrown (see stack-trace below). I am also using a custom workspace, as an FYI.

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08:04:35 Emma: stored 2 report files in the build folder: c:\hudson\jobs\SSO_PNG_UI_CI\builds\2010-12-07_07-57-45\emma
08:04:35 Emma: Coverage: Classes 24/101 (24%). Methods 88/725 (12%). Blocks 966/11959 (8%). Lines 225.2/2248 (10%).
08:04:35 ERROR: Publisher hudson.plugins.emma.EmmaPublisher aborted due to exception
08:04:35 java.lang.NullPointerException
08:04:35 at hudson.plugins.emma.EmmaPublisher.perform(EmmaPublisher.java:132)
08:04:35 at hudson.tasks.BuildStepMonitor$3.perform(BuildStepMonitor.java:36)
08:04:35 at hudson.model.AbstractBuild$AbstractRunner.perform(AbstractBuild.java:603)
08:04:35 at hudson.model.AbstractBuild$AbstractRunner.performAllBuildSteps(AbstractBuild.java:582)
08:04:35 at hudson.model.AbstractBuild$AbstractRunner.performAllBuildSteps(AbstractBuild.java:560)
08:04:35 at hudson.model.Build$RunnerImpl.post2(Build.java:156)
08:04:35 at hudson.model.AbstractBuild$AbstractRunner.post(AbstractBuild.java:529)
08:04:35 at hudson.model.Run.run(Run.java:1349)
08:04:35 at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46)
08:04:35 at hudson.model.ResourceController.execute(ResourceController.java:88)
08:04:35 at hudson.model.Executor.run(Executor.java:139)
08:04:35 Email was triggered for: Failure
08:04:35 Sending email for trigger: Failure
08:04:35 An attempt to send an e-mail to empty list of recipients, ignored.
08:04:35 Finished: FAILURE