I have an IVM system with a 4-port dialogic card that works great, as long as I connect an analog line to it. (I have to use Dialogic, as I have several of them purchased several years ago) Everything works well.
I want to start using an IP based PBX with IVM. I have set up the pbx system with several IP phones including 2 Express Tal stations. Everything seems to be configured ok. All the phones can talk to each other. ExpressTalk can talk to other Express Talk systems as well as other IP phones and vice versa.
However, when the IVM machine is called, it does not work. On the IVM system I can see an incoming call, and then it hangs up.
I have correctly set up the SIP info in IVM, and it registers itself with the PBX.
I've tried this with Axon PBX as well.
The IVM machine servers as an IVR and connects to a database server to retrieve info.
I also need to be able to transfer a call back to any extension after the caller is done with his request.
I'm attaching a diagram of both systems... the analog that works and the IP that does not.
What am I missing?
Here is the image.

I have paid for the platinum support, so I'm hoping the IVM support folks will jump in.
Thanks for any help you can give.
Ray
Link to Image:
Link for large image