EST STOP TXJobManager

Hi All,
we got this error on our B2B 4.0.2 server and our TXJobManager stoped. can anyone give idea on the possible cause and how to handle this kind of runtime errors.
2004-12-07 15:41:20 EST DISABLE
com.wm.app.repo.RepositoryException: com.wm.util.queue.ValuesHashException: java.util.NoSuchElementException
([B2BCORE.0063.9127] [TxMgr] Update)
2004-12-07 15:41:20 EST STOP TXJobManager