XNS Content Store NING

Does anybody know anything about how to create a content store? We would like to devlop a sandbox server that will allow us to minipulate data the way the do on Ning.

I understand (rumor) that they use mysql as repositories for objects in the contect store.

I've searched the internet and have not found anything yet.

xns.org changed to xdi.org and XDI infrastructure now related to identity servers.

So is there some method to store xns data (or xml data) in mysql? If so, how do you set it up?

Thanks for the help

PS, I read the earlier thread:
Database vs. XML, but it doesn't go into how to actually setup the database to do this?