since days I have been searching for answers but couldn't get what I am searching for.

I program a realtime webapp using *Javascript* and *HTML5*. For saving game stats I wanted to use a *XML-file*, that holds all the levelpoints and the achievements *and lies locally within the same folder as the html*. 

So I found out, how to **read** out the values stored in the XML-file with an *XMLHttpRequest*. The problem is, that I can only **change** the node values client-sided, so if I empty the cache or simply reload the page, the XML does hold the original values. 

To **save** the XML server-side is what I want. I hope, you can help me :) 

Thanks in advanced!