I have started to play with OpenPNE, a php based open source SNS. The license is GPL2.0.

Why?

Well, I am thinking of integrating it with ISSO.

Current problem is that the development documentation is so thin, that it is kind of difficult to find out the starting point. I have been doing it for a couple of weeks and finally I am starting to see the file structure.

Anyhow, I will keep posting on the progress.