[CentOS] CentOS-6 dhcpd

I've installed CentOS-6 on my server (in parallel to CentOS-5.6) and now I'm trying to set up dhcpd.

I'm not sure if there has been a change in dhcpd under CentOS-6, but I'm getting the dreaded message "Not configured to listen on any interfaces!" when I "sudo service dhcpd restart".

I realise now that I have never known how the connection between interface (eth0 and eth1, in my case) and network (192.168.1.0 and 192.168.2.0, in my case) is established.

I have DHCPDARGS=eth1 in /etc/sysconfig/dhcpd but evidently I need to say something more somewhere.

Can one actually specify the interface in /etc/dhcpd.conf and if so how?

Any suggestions or enlightenment gratefully received.