Why scm throw exception after changeset associate successed

# scm changeset associate 1017 6549
Link created.
java.lang.IllegalStateException: Job manager has been shut down.
        at org.eclipse.core.internal.jobs.JobManager.schedule(JobManager.java:1104)
        at org.eclipse.core.internal.jobs.InternalJob.schedule(InternalJob.java:427)
        at org.eclipse.core.runtime.jobs.Job.schedule(Job.java:462)
        at com.ibm.team.filesystem.rcp.core.internal.changes.util.listeners.UpdateChangesJob.requestUpdate(UpdateChangesJob.java:151)
        at com.ibm.team.filesystem.rcp.core.internal.changes.update.util.UpdateManager.requestUpdate(UpdateManager.java:77)
        at com.ibm.team.filesystem.rcp.core.internal.changes.util.listeners.EventManager.handleEvents(EventManager.java:611)
        at com.ibm.team.repository.client.util.EventSource$BackgroundEventDispatcher$1.run(EventSource.java:720)
        at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
        at com.ibm.team.repository.client.util.EventSource$BackgroundEventDispatcher.process(EventSource.java:713)
        at com.ibm.team.repository.client.util.EventSource$BackgroundEventDispatcher$3.run(EventSource.java:771)
        at com.ibm.team.repository.client.util.ThreadCheck.runProhibitingLongOps(ThreadCheck.java:174)
        at com.ibm.team.repository.client.util.EventSource$BackgroundEventDispatcher.process(EventSource.java:756)
        at com.ibm.team.repository.client.util.EventSource$BackgroundEventDispatcher$4.run(EventSource.java:790)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:781)
java.lang.IllegalStateException: Job manager has been shut down.
        at org.eclipse.core.internal.jobs.JobManager.schedule(JobManager.java:1104)
        at org.eclipse.core.internal.jobs.InternalJob.schedule(InternalJob.java:427)
        at org.eclipse.core.runtime.jobs.Job.schedule(Job.java:462)
        at com.ibm.team.filesystem.rcp.core.internal.changes.util.listeners.UpdateChangesJob.requestUpdate(UpdateChangesJob.java:151)
        at com.ibm.team.filesystem.rcp.core.internal.changes.update.util.UpdateManager.requestUpdate(UpdateManager.java:77)
        at com.ibm.team.filesystem.rcp.core.internal.changes.util.listeners.EventManager.handleEvents(EventManager.java:611)
        at com.ibm.team.repository.client.util.EventSource$BackgroundEventDispatcher$1.run(EventSource.java:720)
        at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
        at com.ibm.team.repository.client.util.EventSource$BackgroundEventDispatcher.process(EventSource.java:713)
        at com.ibm.team.repository.client.util.EventSource$BackgroundEventDispatcher$3.run(EventSource.java:771)
        at com.ibm.team.repository.client.util.ThreadCheck.runProhibitingLongOps(ThreadCheck.java:174)
        at com.ibm.team.repository.client.util.EventSource$BackgroundEventDispatcher.process(EventSource.java:756)
        at com.ibm.team.repository.client.util.EventSource$BackgroundEventDispatcher$4.run(EventSource.java:790)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:781)