Yes it was not the good one tnsnames.ora. Below, with WLS, Oracle 11gR2 but E1 9.0
JDE900 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = ORAJDE-scan)(PORT = 1521))
(LOAD_BALANCE = yes)
(FAILOVER = yes)
(CONNECT_DATA =
(SERVICE_NAME = JDE900_TAF)
(FAILOVER_MODE =
(TYPE = SELECT)
(METHOD = BASIC)
(RETRIES = 180)
(DELAY = 5)
)
)
)