Oracle : Ошибка ORA-12518

"TNS:listener could not hand off client connection"
*Cause: The process of handing off a client connection to another process
*Action: Turn on listener tracing and re-execute the operation. Verify
that the listener and database instance are properly configured for
direct handoff. If problem persists, call Oracle Support.
*Comment: The problem can be worked around by configuring dispatcher(s)
to specifically handle the desired presentation(s), and connecting
directly to the dispatcher, bypassing the listener.

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