I use XAMPP on Ubuntu 11.04 and is there anyway that I am able to update the PHP from 5.0 to like 5.3.1?
I have tried to get this infos on the Internet but I am not able to find the solution.
Install a newer LAMP (XAMPP) pre-configured package that has what you need from wherever you got your initial package from.
When you work with pre-packaged solutions like this, you're at the will of the packager. It's pretty much always better to install and configure each component individually, that way you can upgrade what you need when you need it and it isn't riddled with extremely insecure defaults like most AMPP packages.