Oracle : Ошибка ORA-28544

28544, 0000, "connect to agent failed, probable Net8 administration error"
*Cause: Net8 reported a failure to make a RSLV connection or
a protocol mode error when the Oracle server attempted
to establish communication with a Heterogeneous Services
agent or an external procedure agent. This usually is due
to an administration error in setting up Net8 service definitions
in TNSNAMES.ORA or LISTENER.ORA: A basic network connection
is opened, but it connects to a program which does not use
the appropriate protocol. This often is a sign that the
connection goes to the wrong program.
*Action: Check Net8 administration in the following ways:
-- When using TNSNAMES.ORA or an Oracle Names server, make sure
that the connection from the ORACLE server uses the correct
service name or SID.
-- Check LISTENER.ORA on the agent's host machine to assure that
the service name or SID refers to the correct agent
executable in its (PROGRAM=...) clause.
-- Confirm in TNSNAMES.ORA or the equivalent service definition
that sevice 'extproc_connection_data' does NOT contain
(HS=), or that the service definition used by a
Heterogeneous Services database link DOES contain (HS=).

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