Unable to find the command readarray

Issue

• Unable to find the command readarray, below are the output's of few command's which might help.

[root@localhost ~]# rpm -qa |grep bash
bash-3.2-33.el5_11.4
[root@localhost ~]# cat /etc/redhat-release
Red Hat Enterprise Linux Server release 5.10 (Tikanga)
[root@localhost ~]# uname -a
Linux localhost 2.6.18-371.11.1.el5 #1 SMP Mon Jun 30 04:51:39 EDT 2014 x86_64 x86_64 x86_64 GNU/Linux
[root@localhost ~]# rpm -qa |grep bash
bash-3.2-33.el5_11.4
[root@localhost ~]# yum list bash
Loaded plugins: rhnplugin, security
This system is receiving updates from RHN Classic or RHN Satellite.
Installed Packages
bash.x86_64                                                                                 3.2-33.el5_11.4                                                                                 installed
[root@localhost ~]# help -m readarray
-bash: help: -m: invalid option
help: usage: help [-s] [pattern ...]
[root@localhost ~]#