Oracle 10g Listener problem In Oracle 10g I have a listener problem,

Here is tnsnames.ora :

MYTNS =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = 
       (PROTOCOL = TCP)
       (HOST = testiold)
       (PORT = 1521)
      )
    )
    (CONNECT_DATA =
      (SERVICE_NAME = mysid)
    )
  )

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


and the listener.ora:

SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (GLOBAL_DBNAME = mysid)
      (ORACLE_HOME = /oracle/10.2.4/db/OraHome_1)
      (SID_NAME = mysid)
    )
  )

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


The proble is I cannot start the listener with this configs, when I try lsnrctl start I got this:

LSNRCTL for IBM/AIX RISC System/6000: Version 10.2.0.1.0 - Production on 14-AUG-2012 22:11:44

Copyright (c) 1991, 2005, Oracle.  All rights reserved.

Starting /oracle/10.2.4/db/OraHome_1/bin/tnslsnr: please wait...

TNSLSNR for IBM/AIX RISC System/6000: Version 10.2.0.1.0 - Production
System parameter file is /oracle/10.2.4/db/OraHome_1/network/admin/listener.ora
Log messages written to /oracle/10.2.4/db/OraHome_1/network/log/listener.log
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=testiold)(PORT=1521)))

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=testiold)(PORT=1521)))
TNS-12535: TNS:operation timed out
 TNS-12560: TNS:protocol adapter error
  TNS-00505: Operation timed out
   IBM/AIX RISC System/6000 Error: 78: Connection timed out


and whenever I try to connect to DB it says:

ORA-28547: connection to server failed, probable Oracle Net admin error


Can you please help me?
As Phil Says I replaced hostname with Actual IP but the connection prblem was for 

(PROGRAM = extproc)


In listener.ora file, Removing it solved the issue.

To let external procedures work these changes should be done:

Adding new SID entry in SID_LIST_LISTENER SID_LIST with SID_NAME = SID in tnsnames.ora at EXTPROC_CONNECTION_DATA and PROGRAM = extproc and a proper ORACLE_HOME(Environment variables can be added)

In ADDRESS_LIST in LISTENER part of listener.ora new ADDRESS Entry should be added with PROTOCOL = ipc and KEY = EXTPROC