Messages server proxy65 behind NAT?

Question

Hi,
How do I get the proxy65 service usable from the internet? It's natted, here's my setup:
I have a messages server runing on x.x.x.x. (private IP)
I have a router that forwards traffic on ports 5222,...,7777 from the public IP y.y.y.y
My proxy65 configuration in /Library/Preferences/com.apple.Proxy65.plist  can only accept the ip x.x.x.x as it cannot bind to the external IP.
The messages server advertises the proxy as <streamhost port='7777' host='x.x.x.x' jid='proxy65.domain.com'/>
and that is obviously not usable from outside.
Is there a way to advertise the external IP of the messages host so that wan clients can send files to lan clients?
Thanks,
Anton.

Answer 1

Update:
I commented out this:
    socket.inet_pton(socket.AF_INET, ip)
in this:
/Applications/Server.app/Contents/ServerRoot/usr/share/proxy65/proxy65.py
and now my
/Library/Preferences/com.apple.Proxy65.plist   
can use a hostname instead of IP like so:
<dict>
        <key>jid</key>
        <string>proxy65.domain.com</string>
        <key>proxyips</key>
        <string>xmpp.domain.com:7777</string>
so now all works from the outside and from the inside.