IAX trunk

ok i have 2 asterisk@home servers setup A & B

A has a digium card with 3 ports 2 pot one analog
B has only sip phones

B phones can call out A server pot lines A server can call B server sip phones
how do i enable an inbound call to server A pot line and dial an extention on the B server then the B server sip phone get a ring?

server a logs no context/extentions

configs are same so i should be able to call in and dial 32XXX to connect to the B server’s extentions