I seem to be able to connect locally using `sqlplus lee/$password@lee3
using SQL*Plus, but I get the following error when I use iSQL*Plus:

   ORA-12162: TNS:net service name is incorrectly specified

I've seen plenty of similar posts on Google, but none of them have shed
any light on the matter. My TNSNAME and LISTENER files are shown
below... can anyone tell me where the problem lies?

--- BEGIN TNSNAMES.ORA -------------------
LEE3 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = metal)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = lee3)
    )
  )

EXTPROC_CONNECTION_DATA =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC))
    )
    (CONNECT_DATA =
      (SID = PLSExtProc)
      (PRESENTATION = RO)
    )
  )
--- END TNSNAMES.ORA -------------------

--- BEGIN LISTENER.ORA -------------------
SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = PLSExtProc)
      (ORACLE_HOME = /metal0/app/oracle/product/10.2.0/Db_1)
      (PROGRAM = extproc)
    )
  )

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

--- END LISTENER.ORA -------------------