Cant connect using sqlplus from the server if using IP in the listener.ora file

Hi,

We have a 11g R2 database on Linux

The server IP address is xxx.yyy.zzz.3
The hostname of the server is

$hostname

linuxOracle

Here is the listener.ora

SID_LIST_LISTENER
  (SID_LIST =
    (SID_DESC =
      (GLOBAL_DBNAME = orcl)
      (ORACLE_HOME = /u01/app/oracle/product/11.2.0/dbhome_1)
      (SID_NAME = ORCL)
    )
  )
LISTENER =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = linuxOracle)(PORT = 1521))
  )

Here is the tnsnames.ora


ORCL =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = xxx.yyy.zzz.3)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = orcl)
    )
  )


The problem is that when we use the IP address in the listener.ora file, and we try to connect using sqlplus