XMPP clients connect but messages never get through [SOLVED]

I am having some problems getting ejabberd 14.07 working on my CentOS 7 box. I got everything installed and it appears to be running properly from the server side, but now I am having problems getting messages through the system. I suspect it's a networking issue, but I don't know how to diagnose it. Any help would be greatly appreciated.

The basics:
CentOS 7 sitting at home behind a firewall/NAT router.
CentOS box has the following ports open in firewalld: 5222, 5269, 5280, 4369, 4560
My firewall/router is configured to route ports 4560, 5222, 5269 and 5280 to the CentOS box
I have SRV records configured for the domain:
_xmpp-client._tcp.mydomain.net 86400 IN SRV 0 5 5222 www.mydomain.net
_xmpp-server._tcp.mydomain.net 86400 IN SRV 0 5 5269 www.mydomain.net
www.mydomain.net has a DNS record that returns my external IP address
The CentOS box has an /etc/hosts entry that maps www.mydomain.net to its own address on the internal network (192.168.2.61)

When I tail /var/log/ejabberd/ejabberd.log, I can see the two clients connecting. When one of them tries to send a message to the other, I see the following:

2015-04-14 13:53:15.799 [debug] <0.446.0>@ejabberd_c2s:send_text:1820 Send XML on stream = <<"\nsadsadasd\n\ndread\n">>
2015-04-14 13:53:17.779 [info] <0.451.0>@ejabberd_s2s_out:handle_info:990 Reconnect delay expired: Will now retry to connect to www.mydomain.net when needed.

What am I doing wrong here? I have been beating my head against the wall since last night. I thought the SRV records would fix the problem, but so far no joy.

Thanks,
Dave