I noticed this when investigating issue 4325 (NullPointerException when polling). The
page project/scmPollLog displays only:
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Last Team Foundation Server Polling Log

Started on 2009-aug-28 08:40:18
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but in the console output (running through mvn hpi:run) i got this exception:
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2009-aug-28 08:40:18 hudson.triggers.SCMTrigger$Runner runPolling
ALLVARLIG: Failed to record SCM polling
java.lang.NullPointerException
at hudson.plugins.tfs.TfTool.execute(TfTool.java:99)
at hudson.plugins.tfs.model.Server.execute(Server.java:47)
at hudson.plugins.tfs.model.Project.getDetailedHistory(Project.java:41)
at hudson.plugins.tfs.TeamFoundationServerScm.pollChanges(TeamFoundationServerScm.java:187)
at hudson.model.AbstractProject.pollSCMChanges(AbstractProject.java:965)
at hudson.triggers.SCMTrigger$Runner.runPolling(SCMTrigger.java:312)
at hudson.triggers.SCMTrigger$Runner.run(SCMTrigger.java:339)
at hudson.util.SequentialExecutionQueue$QueueEntry.run(SequentialExecutionQueue.java:114)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:885)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
at java.lang.Thread.run(Thread.java:619)
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The exception or an error message should be displayed in the SCM Poll page, so the user
can easily see that something went bad when polling. Right now it looks like the polling
is still going.