If you have port 4445 forwarded then it should work just fine, as long as the port is the same (port 4445 in the router, to port 4445 in the server).
Not sure what to tell you, but if you forwarded port 4445 , then it can be accessed from remote. I do it all the time. Perhaps you have some iptables rules at the server preventing access to port 4445 ?
