Magento Mcrypt Extension Issue

Last week When I was making one of magento project live I had to shift entire code to production server. Code was running fine except a small issue.
 When I  login on checkout page, after adding items in my cart, it sends me back to cart url with a blank page. Looking at apache logs revealed -
 Call to undefined function mcrypt_module_open() in /var/www/html/domain.com/lib/Varien/Crypt/Mcrypt.php on line 63, referer: http://domain.com/checkout/onepage/index/

Solution -
How to install php mcrypt extension. 
Couldn't find any pre-built packages.

1 .Download Following RPM Packages -

# wget http://dl.fedoraproject.org/pub/epel/6/x86_64/php-mcrypt-5.3.3-1.el6.x86_64.rpm
# wget http://dl.fedoraproject.org/pub/epel/6/x86_64/libmcrypt-2.5.8-9.el6.x86_64.rpm

2. Install - 

yum localinstall php-mcrypt-5.3.3-1.el6.x86_64.rpm libmcrypt-2.5.8-9.el6.x86_64.rpm 

Ref -
http://injustfiveminutes.wordpress.com/2012/11/23/install-php-mcrypt-extension-on-rhel-6/