Because I’m a nice guy I will share this command with you:

[me@it ~]# yum install php-imap

Now it’s installed, proof:

[me@it ~]# php --ri imap
 
imap
 
IMAP c-Client Version => 2004
SSL Support => enabled
Kerberos Support => enabled
[me@it ~]#

If it wasn’t installed it would have shown you:

[me@it ~]# php --ri imap
Extension 'imap' not present.

But of course it isn’t working… yet, untill you restart the Apache server daemon

[me@it ~]# service httpd restart

And because I’m a nice guy I will tell you where I found the first command before even you ask: http://www.php.net/manual/en/imap.setup.php

The PHP manual is always a good place to start, oh… and don’t underestimate comments.

In order to install PHP 5.2.6 you can add the CentOS testing repository and enable it then install or update PHP.

To add the CentOS testing directory, create a file /etc/yum.repos.d/centos-test.repo and add this line:

[c5-testing]
name=CentOS-5 Testing
baseurl=http://dev.centos.org/centos/5/testing/$basearch/
enabled=1
gpgcheck=1
gpgkey=http://dev.centos.org/centos/RPM-GPG-KEY-CentOS-testing


Then install or update PHP:

[root@server ~]# yum install php

or

[root@server ~]# yum update php

Then you can disable the testing repo by editing the file and setting the option “enabled” to “0″

[c5-testing]
name=CentOS-5 Testing
baseurl=http://dev.centos.org/centos/5/testing/$basearch/
enabled=0
gpgcheck=1
gpgkey=http://dev.centos.org/centos/RPM-GPG-KEY-CentOS-testing