This is around about way to deal with Verizon that has worked in the past. Open a trouble ticket for the Centrex service not working. When they close the ticket in repair for not having Centrex service on the T-1 open another ticket refering to the first and Escalate, escalate, then escalate! Do not allow them to close the ticket until a manager or a third line speaks to you. repair can get you intouch with the correct people faster than a sales agent or a customer service coach. Tell them you need Centrex ISDN service. This is marketed as Intellipath.