Its like any other gateway config, nothing extra. Your config would look something like this.
interface FastEthernet0/0.63
description Interface for IP Phones
encapsulation dot1Q 63
ip address 192.168.63.254 255.255.255.0
h323-gateway voip interface
h323-gateway voip id GKPR ipaddr 192.168.60.254 1718
h323-gateway voip h323-id chicagogtwy
h323-gateway voip tech-prefix 5#
h323-gateway voip bind srcaddr 192.168.63.254
dial-peer voice 9999 pots
destination-pattern 9T
port 1/0:23
dial-peer voice 0111 voip
destination-pattern 011T
session target ras