inetd

First you need to edit the file /etc/services, which contains information regarding the known services available in the Internet to add the following line:

zonecheck       1904/tcp  # ZoneCheck service

You also need to configure inetd, so that it is listening for the new zonecheck service, this is done by adding the line:

zonecheck stream tcp nowait root /usr/local/bin/zonecheck zonecheck --INPUT=inetd

If you have an IPv6 stack installed but don't have the connectivity with the outside world add the option -4 to the zonecheck command.