Call routing through asterisk server to trixbox servers

Hi,

I have 3 trixbox Servers : machine A, machine B & machine C

1 asterisk Server: machine D running version 1.4

1 Ayaya Server: machine E running G3Si v9.0

The communication among machines A,B & C to D is via IAX trunks whilst the comunication between machines D & E is via PRI.

The problem I am having is when Machine A or B or C places an initial call to each other; the call does not go thru. The call should be routed to Machine D which is then supposed to route the call to machine A or B or C ie. [A|B|C -> D-> B,C|A,C|A,B]. However it appears that for the call to take place it needs a “wakeup” from machine D before the call can take place via the Dial command. If the “wakeup” is not given the call appears “congested”. The reason for machine D is so that the extensions and protocols on the Avaya server can be executed as well as having a central system for routing calls. Once all machines are given a wakeup call, everything works fine.

How do we overcome using this wakeup procedure?