How do I setup an XMPP server for Facebook that returns JSON?

In a nutshell, here is what I want to do:

1. Query a URL like www.mysite.com/?action=GetOnlineList&access_token=[Facebook Token]
2. Have that URL then return a list of all the user's Facebook friends online in JSON

I could then also do some other actions like "SendMessage" and "GetMessages" as well.

I've been reading up on this for a while and so far I've gathered that I will need XMPP/Jabber to do this, but I don't know exactly where to start.

Would creating an OpenFire server allow me to do this? I'm not familiar with XMPP at all, so I don't know how I'd be able to spit out JSON data from the server. Would I be able to setup queries like that on an OpenFire server?