ORA-25316: Late in the current transaction to begin an Enqueue/Dequeue operation
Cause : Check if the Enqueue/Dequeue operation is performed via triggers on Materialized Views which isn't supported.
Action - How to fix it : DBA Scripts :: www.high-oracle.com/scripts
Triggers on materialized views aren't supported. Workarounds are on-demand materialized views or execution of trigger code within an autonomous txn.