Using multiple domains (and mx records) with dnsmasq

I've followed the split_DNS article (very helpful), but I need my zimbra server to work with 2 domains.

I have both entered in /etc/hosts, but I'm not sure how to format dnsmasq.conf to handle both domains and both mx-hosts. Are they all one line separated by comma, or multiple lines? Does anyone have a simple example I can look at? Everything with the first domain and mx-host is working great, but I need to add a second and need some guidance.

Thanks,
James