XAMPP is a package for developing and testing.
It is only supported here as full package, because the configuration of each component is balanced on each other.
Upgrade of a single component isn't described in any of the requests.
If you want to use PHP v5.3.1, then you must wait for the next release (or use the Beta), or you had to try it on your own (which i wouldn't recommend to you)
We don't provide any support via personal channels like PM, email, Skype, TeamViewer!It's like porn for programmers