We are running IOS 12.4(3g) with CME 3.3 on Cisco 2811 routers. The router is connected to analog phone lines via FXO ports and we have a few analog phones connected via FXS ports and the IP phones are 7960. The issue is that when a 7960 phone conferences in one of the analog phones on the CME the 7960 phone is no longer able to pass DTMF tones to navigate through IVRs etc. The DTMF phones from the analog phones connected to the FXS ports work fine. Has anyone ran into this scenario and does anyone have a resolution?