Cisco Systems 3600 do not configure store and forward tone., DTMF signals.

Voice over IP Configuration Examples
VC-44 Voice, Video, and Home Applications Configuration Guide
voice-port 1/0/1
signal immediate
operation 4-wire
type 2
!Configure the serial interface
interface serial 0/0
description serial interface type dce (provides clock)
clock rate 2000000
ip address 172.16.1.123
no shutdown
Configuration for Router SLC
hostname saltlake
!Configure pots dial peer 1
dial-peer voice 1 pots
destination-pattern 119....
port 1/0/0
!Configure pots dial peer 2
dial-peer voice 2 pots
destination-pattern 119....
port 1/0/1
!Configure voip dial peer 3
dial-peer voice 3 voip
destination-pattern 555....
session target ipv4:172.16.1.123
!Configure the E&M interface
voice-port 1/0/0
signal immediate
operation 4-wire
type 2
voice-port 1/0/0
signal immediate
operation 4-wire
type 2
!Configure the serial interface
interface serial 0/0
description serial interface type dte
ip address 172.16.65.182
no shutdown
Note PBXs should be configured to pass all DTMF signals to the router. We recommend that you
do not configure store and forward tone.
Note If you change the gain or the telephony port, make sure that the telephony port still accepts
DTMF signals.