well... web server sound much more appropriate.. when u talking just server, it is quite confusing.
EDiT: Client u use to connect to server? It is not connect using http protocol. U already mention on above. Http protocol is web-server. Not a game server. So. It is impossible the client to connect thru http.
It only can connect using the domain (since u not use the public IP, but u need to appoint public IP to domain). But at the end. It is using login server port as written in the clientinfo.xml - not thru http.
So, in ur clientinfo.xml, u need to alter the connection part. Since u want to run 2 servers. It should be like following
<connection>
</connection
<connection>
</connection>
And in here.. the login server port it cant be on same port 6900. It should be 6900 and something. But on local network. U can have 6900 coz on 2 different computer. But on public network. U only can have 1 login server port configure as 6900 on ur modem.
Additional Note: unless.. if u are running on 2-3 servers but using the same login server port. It will become like in official - on single id. U can select choose on different server.