I just came across your post and was wondering if you made it work. We are using the D/240 and D/480 Dialogic cards and we did not set them up as ISDN. Our's is set up as AMI-basic, D4, Robbed-bit, Mulaw, Idle code 11111111, Near-end CSU Type: Other. Each of the 24 ports on each T-1 is set up just like an extension with the type set at VRUFD. The Software guys had to play with the signalling a little, but it works fine. We were even able to strip the EWT and QPOS off and send to our SQL server for display on our Web site.
Hope this is a help, I would be happy to send you our configuration data for the VRUs and the Definity.