two ways to solve this as well.

1. NAT the 44. address out the public internet. That is what I am doing

here.

That only works when you have made special arrangements (policy routing) to make sure the Echolink traffic is ALWAYS sent to the NAT device and never routed directly. See what I explained to Gustavo.

2. have the server have two NIC cards. One with a 44 address and the

other a local non-routable which is then NATed ouot your public internet IP.

That does not require 2 cards (you can put 2 addresses on 1 card), and it is basically the same as the policy routing method, in this case using the IP address as the base for the policy routing. In practice it can be more difficult to implement because you need to force the Echolink application to bind to the correct card address. Fortunately Svxlink can do that, but many other programs cannot.

Rob