I've been programming a game that I want to take to a network setting. It would require a server to be used for this application, in my opinion.

I'm "familiar" with network programming--I've used C/C++ to a limited extent with TCP/UDP transmissions--but hardly "experienced". So I do know to some extend what I'm getting myself into here, but I'm looking for a little more advice.

The game is simple, probably in the range of 4-12 players to start, but I might like to expand beyond that if the server is powerful enough, once everything is up and running.

I'm trying to choose a language to program the server in. Right now the game is in Flash--it may change at some point, but not for the foreseeable future.

Anyway, I'm aware of a few options, namely C, C++, Java, C#. I'm generally a strong programmer in C/C++, it's been a while since I've done Java, and C# is basically foreign to me. (except for my background in C/C++)

I'm just wondering what advice people generally have choosing between those, and any other languages that are good for server-based games. I'm very much open to looking at a new (or revisiting a forgotten) language, to enhance my programming versatility, but I would like to get started somewhat soon. I've seen some pros/cons listed elsewhere but I wanted to come to the game programming board here, as I don't know who else would have more experience/knowledge than people on a board like this.

Thanks in advance for all the advice!
-Tux