Request to Payment Program is failing very frequently with OPP error

 Hi All,

One of our custom program "Request to Payment Program" is failing very frequently with below Error.

REP-0300: ORACLE error occurred.
REP-0069: Internal error
REP-57054: In-process job terminated:Terminated with error: 
REP-300: ORACLE error occurred.

+------------- 1) PUBLISH -------------+
Beginning post-processing of request 1494991 on node *********** at 29-MAY-2012 09:36:11.
Post-processing of request 1494991 failed at 29-MAY-2012 09:36:12 with the error message:
One or more post-processing actions failed. Consult the OPP service log for details.
+--------------------------------------+

But the OPP log the entry about the request is 

Output type:   EXCEL
[5/29/12 9:36:12 AM] [UNEXPECTED] [57359:RT1494991] java.io.FileNotFoundException: /pwncti/applcsf/out/PWNCTI_auohswnct09/o1494991.out (No such file or directory)
	at java.io.FileInputStream.open(Native Method)
	at java.io.FileInputStream.<init>(FileInputStream.java:106)
	at oracle.apps.fnd.cp.opp.XMLPublisherProcessor.process(XMLPublisherProcessor.java:274)
	at oracle.apps.fnd.cp.opp.OPPRequestThread.run(OPPRequestThread.java:173)

[5/29/12 9:36:12 AM] [57359:RT1494991] Completed post-processing actions for request 1494991.