BUILD PROGRAM ERROR - CANNOT VALIDATE DOCUMENTS

 Hi - just wondering if anybody has run into this error - it just starting happening to us today and there haven't been any patches or environment changes for weeks.  The log file does not provide much detail:

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Payments: Version : 12.0.0

Copyright (c) 1979, 1999, Oracle Corporation. All rights reserved.

IBYBUILD module: Build Payments
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Current system time is 28-MAY-2013 13:01:22

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**Starts**28-MAY-2013 13:01:23
**Ends**28-MAY-2013 13:01:24
BUILD PROGRAM ERROR - CANNOT VALIDATE DOCUMENTS
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Start of log messages from FND_FILE
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Enter Build :: Concurrent Request ID::593720
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|STEP 1: Insert Payment Service Request:: Timestamp:13-05-28 13:01:23,829195000 -03:00|
+-----------------------------------------------------------------------------------------------------+
+----------------------------------------------------------------------------------------------------+
|STEP 2: Insert Documents :Timestamp:13-05-28 13:01:23,839264000 -03:00|
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+--------------------------------------------------------------------------------------------------------+
|STEP 3: Account/Profile Assignment :Timestamp:13-05-28 13:01:24,538330000 -03:00|
+--------------------------------------------------------------------------------------------------------+
Request status after assignments: ASSIGNMENT_COMPLETE
+----------------------------------------------------------------------------------------------------+
|STEP 4: Document Validation :Timestamp:13-05-28 13:01:24,556360000 -03:00|
+----------------------------------------------------------------------------------------------------+
Exception occured when validating documents. Document validation will be aborted and no document statuses will be committed for payment request 633
SQLCODE: 1
SQLERRM: User-Defined Exception
Build program error: Exception occured when attempting to validate the