problem with listener

[Sameer]

Check if the service_name parameter specified in listener.ora is same as that of in init.ora (parameter service_names)

If you haven't specified SERVICE_NAMES parameter in init.ora then change SERVICE_NAME of tnsnames.ora to SID

listener.ora

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS_LIST =
        (ADDRESS = (PROTOCOL = TCP)(HOST = stmn)(PORT = 1521))
      )
    )
  )

SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = orcl)
      (ORACLE_HOME = /opt/oracle/product/8.1.6)
    )
  )

tnsnames.ora

ora4 = 
(DESCRIPTION =
 (ADDRESS_LIST =
   (ADDRESS =
      (COMMUNITY=TCP.world)
      (PROTOCOL=TCP)(Host=stmn)
      (Port=1521)
    )
 )
 (
  CONNECT_DATA=(SID=orcl)
 )
)

HTH

Sameer