Did you disable the system triggers before migrating? The best way to perform the migration is to migrate to the base version and then make sure that you were able to open the database and so, then proceed with the application of patch set to the migrated database.
I'm surpries that oracle had suggested the migration to the patched database instance directly. If you don't mind can you pass me the metalink doc id. Just curious to see.
My rule of thumb is first migrate to the base version and then make sure that the application can function, then proceed applying the patchset to the migrated database.
Sam
