Bridge two channels

I am new to freepbx and i am trying to setup a pbx with the latest freepbx distro(asterisk 11.x).
This is the scenario
An Ip Phone has 4 simultaneous incomming calls (ext 1000,ext 2000,ext 3000 and ext 4000) and i need to bridge two of them ,say ext 1000 with ext 3000.
i searched a lot but found no example,only the asterisk bridge command and dont know how to use it.
Any help would be great.
Thank you