Upgrading PHP 5.3.3 to 5.4.4 in CentOS 6.4

I'm using CentOS 6.4 (centos-release-6-4.el6.centos.10.x86_64). I'm trying to upgrade the php version from 5.3.3 to 5.4.4 by using:

yum upgrade php-mysql php-devel php-gd php-pecl-memcache php-pspell php-snmp php-xmlrpc php-xml

and

yum upgrade php

...but this is the only message i'm getting:

Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * base: centos.netnitco.net
 * extras: mirror.wiredtree.com
 * updates: mirror.thelinuxfix.com
Setting up Update Process
No Packages marked for Update

I already ran:

yum update

and everything is in order. I also checked for exclusions of php-* in /etc/yum.conf but nothing was found. Any ideas? Thanks!

Update: solution

Thanks to @mirkobrankovic I ended doing this (on a 64-bit OS):

wget http://download.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
rpm -ivh epel-release-6-8.noarch.rpm
wget http://rpms.famillecollet.com/enterprise/remi-release-6.rpm
rpm -Uvh remi-release-6*.rpm
yum --enablerepo=remi upgrade php-mysql php-devel php-gd php-pecl-memcache php-pspell php-snmp php-xmlrpc php-xml

Maybe this question can help you.
Use the remi repository, you can't get it from CentOS base.
How to add remi repo

To update PHP 5.3.3 to 5.4.4:

wget http://download.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
rpm -ivh epel-release-6-8.noarch.rpm
wget http://rpms.famillecollet.com/enterprise/remi-release-6.rpm
rpm -Uvh remi-release-6*.rpm
yum --enablerepo=remi upgrade php-mysql php-devel php-gd php-pecl-memcache php-pspell php-snmp php-xmlrpc php-xml