new comer looking for help with ejabberd & riak

Howdy people?

So we have been using socket.io, nodejs and mongo so far but we are looking to use XMPP with an ejabberd server since that seems to be the popular choice and perhaps Riak as the backend database. Given that we are new to all of this, would really appreciate if someone could share the right references / repo of the actual code of a chat app using Ejabberd with Riak?

Also, we continue to use node and mongo so we are wondering whether Riak can support user profile management well along with may be other data that we would otherwise save in say Mongo?

Would really appreciate your help as we are looking to re-write our chat and other real time components rapidly to meet deadlines.

thanks in advance

cheers
Sudhama