[syslog-ng]relay host not reporting itself as IP

Greetings, What options should I use in order to make a relay host report itself as it's IP and not hostname? I have a centralized server and various parsing scripts that expect ip addresses as a source, but for some reason, the actual remote syslog servers are logging it's information as its hostname, and not ip. What options, or websites should I check out to read more about the configuration options for ng? Thanks in advance,