How to add php 5.3.10 (or higher) to 1 and 1 Basic Linux and Plesk Platform?

How do I install another version of PHP (5.3.10 or higher) on an existing centOS configuration? I don't want to remove 5.3.3 and I want to make both versions available based on what web application I install per domain.

I want to install Joomla and CB to my virtual server at 1 and 1 hosting site. I have basic knowledge and can run command lines as needed. But, I am not a coder or advanced in other areas of such server.

I have a virtual server with 1 and 1 and they install by default CentOS 6 with Parallels Plesk Panel 12 (64-bit) which includes a patched version of php 5.3.3 (but nothing coded higher).

When I go to install the available applications on one of the domain accounts I want to install Joomla (WordPress works fine on another domain) so I can put community builder on top of the Jommla. But, Joomla won't install since it see's php 5.3.3 (patched) and wants 5.3.10 at a minimum.

The 1and1 Plesk that is installed does not upgrade the php in the Parralles installer.

By command line instructions what can I do to:
- "ADD" a higher version of php (while retaining the patched 5.3.3 to keep plesk happy)
- How to make both versions available when I configure the hosting for an account.

Sorry, I have posted this in the wrong forum.

Please understand we do not provide general support, but support for our products only. We can not advise you on hosting matters. You will need to contact 1&1.

With that said 1&1 appears to have the following tutorials for upgrading PHP.

help.1and1.com/servers-c37684/parallels-plesk-c37703/using-the-product-c85155/update-php-on-your-1and1-server-using-plesk-a730997.html

help.1and1.com/hosting-c37630/scripts-and-programming-languages-c85099/php-c37728/change-the-default-version-of-php-in-the-control-panel-a792330.html