[Freeswitch-users] transfer/bridge in a conference

What's the best way of implementing this scenario: In conferenceA there are user1 and user2, in conferenceB there is user3. How to create 3-way conference with all 3 users and then "transfer?" user2 to confereceB. User1 has to stay in conferenceA after the "transfer" so next call can be taken in conference A while user2 and user3 still talk in conference B. I have thought of creating a new conference C where all parties could talk and "lock" Conferences A and B till user 1 comes back to conference A and user 3 comes back to conference B (user 3 will hangup the call and conference C will be closed/finished) Hope this makes sense.. I am using JavaScrip/Node.js to develop this. All hints and help will be appreciated