listener.ora:

SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = PLSExtProc)
      (ORACLE_HOME = C:\oracle\product\10.1.0\db_1)
      (PROGRAM = extproc)
    )
	(SID_DESC =
      (SID_NAME = nvdvel)
      (GLOBAL_DBNAME = nvdvel)
      (ORACLE_HOME = C:\oracle\product\10.1.0\db_1)
    )
  )

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS_LIST =
        (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.7.43)(PORT = 1521))
      )
      (ADDRESS_LIST =
        (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC))
      )
    )
  )

tnsnames.ora:
# tnsnames.ora Network Configuration File: C:\oracle\product\10.1.0\db_1\network\admin\tnsnames.ora
# Generated by Oracle configuration tools.

EXTPROC_CONNECTION_DATA =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC))
    )
    (CONNECT_DATA =
      (SID = PLSExtProc)
      (PRESENTATION = RO)
    )
  )

NVDVEL =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.7.43)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = nvdvel)
    )
  )


Y:\>lsnrctl status

LSNRCTL for 32-bit Windows: Version 10.1.0.2.0 - Production on 02-MAY-2007 08:44:28

Copyright (c) 1991, 2004, Oracle.  All rights reserved.

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=172.16.7.43)(PORT=1521)))
STATUS of the LISTENER
------------------------
Alias                     LISTENER
Version                   TNSLSNR for 32-bit Windows: Version 10.1.0.2.0 - Production
Start Date                02-MAY-2007 08:41:21
Uptime                    0 days 0 hr. 3 min. 6 sec
Trace Level               off
Security                  ON: Local OS Authentication
SNMP                      OFF
Listener Parameter File   C:\oracle\product\10.1.0\db_1\network\admin\listener.ora
Listener Log File         C:\oracle\product\10.1.0\db_1\network\log\listener.log
Listening Endpoints Summary...
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=172.16.7.43)(PORT=1521)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(PIPENAME=\\.\pipe\EXTPROCipc)))
Services Summary...
Service "PLSExtProc" has 1 instance(s).
  Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service...
Service "nvdvel" has 1 instance(s).
  Instance "nvdvel", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully