Oracle and network detection

I recently had to do a rhel server setup for Oracle 10g. I'd configured static networking for the server but Oracle started complaining I had dhcp set for the NIC. I verified my network settings and tried again but it still kept complaining about the same. Finally I added an entry to the /etc/hosts file and Oracle was happy about it. I don't understand the logic in looking at the /etc/hosts file to determine whether the network configuration is static or dhcp. But anyhow "it works" :)