We recently upgraded from CM 4.2 to 7.0(1). We did not change our trunking (T1 PRI) via 6608. A user called Verizon Wireless on his Cisco 7940 phone. The Verizon auto attendant required his cell phone number be entered by the phone. It did not recognize any keypad entries, however an analog phone (ATA) off the same switch using the same routing could sent DTMF. The Verizon auto attendant didn't recognize any entries from other Cisco VOIP phones (7940, 7911). Any ideas why?