Submit Accounting Programs ends with Warning

Below is the only message I can see in the log file which leads the Submit Accounting Program to ends in Warning.
The only closest Note ID I can find on metalink is ID 1073836.1
Why this warning is happening......? How can I fix this??

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The following REVERSAL events could not be processed. The event/process status is U/U: 
Note: this warning may be ignored for any events whose ledger is a cash-basis ledger
-------NO SUCH EVENTS-----------
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16-NOV-2012 17:35:42 - executing postprocessing hook
ARP_XLA_EXTRACT_MAIN_PKG.postprocessing()+
ARP_XLA_EXTRACT_MAIN_PKG.postprocessing()-
event key = 789-6693490-CEA7CF43B3CF6739E04400144FFAFF84
16-NOV-2012 17:35:42 - postprocessing hook executed successfully
16-NOV-2012 17:35:42 - Completing Journal Entries
16-NOV-2012 17:35:42 - Checking status of the parent Accounting Program
16-NOV-2012 17:35:42 - Dequeuing the unit from the queue
16-NOV-2012 17:35:42 - Submitting the transfer to GL
GL Inerface tablename = XLA_GLT_262315
GL Inerface tablename = XLA_GLT_262315
tablename = XLA_GLT_262315
16-NOV-2012 17:36:08- Submitting the Journal Import
16-NOV-2012 17:36:53- Journal Import completed 
16-NOV-2012 17:36:53 -  End of the transfer