patch 14232224 it fails with :Error message is ORA-01442: column to be modified to NOT NULL is alre

Hi,
When applying patch  14232224 it fails with :
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ATTENTION: Please fix the above failed worker(s) so the manager can continue.

Current time is: Wed Sep 12 2012 23:48:05
[aptst510@lapebs02 log]$ tail -20 adwork001.log
 ALTER TABLE CLL.CLL_F033_PAY_RETURN_HEADERS MODIFY ( RETURN_ID  NOT NULL  )

Start time for statement above is Wed Sep 12 23:48:04 COT 2012
End time for statement above is Wed Sep 12 23:48:04 COT 2012
Error in executing statement ALTER TABLE CLL.CLL_F033_PAY_RETURN_HEADERS MODIFY ( RETURN_ID  NOT NULL  )
Error message is ORA-01442: column to be modified to NOT NULL is already NOT NULL

Error code is    1442
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Done calling the utility function. Return Code = [1] TimeStamp = [Wed Sep 12 23:48:04 COT 2012]