Hi! I tried #!subst "/IPADDRESS_VIRTUAL/83.136.32.161/" listen=udp:IPADDRESS_VIRTUAL:5060 and #!define IPADDRESS_VIRTUAL 83.136.32.161 listen=udp:IPADDRESS_VIRTUAL:5060 Both do not work - am I doing something wrong or is this a known limitation with "listen" statements? Thanks Klaus