I want to create a public dedicated server. I'm running on a linux box with the latest Mandrake behind a netgear RT314 router/firewall. I've searched around and can't find any information hardly at all on what needs (if anything) to be configured in firewalls to let people connect to my JK2 server.

Somebody at one point was talking about putting together a HOWTO. Did that ever actually happen?

Assuming you already have a firewall up using iptables, your default input policy is deny/drop and your default output policy is accept (not good form, but standard practice nonetheless), and you accept established/related connections, you would issue the following commands (or very similar):

/sbin/iptables -A INPUT -p TCP -s 0/0 --dport 29070 -j ACCEPT
/sbin/iptables -A INPUT -p UDP -s 0/0 --dport 29070 -j ACCEPT

Creating a comprehensive firewall ruleset is beyond the scope of this forum, if you need help with that, please visit www.linuxdocs.org) and rtfm.

edit: bah, i misread your post. To answer your question, you simply want to forward all traffic on port 29070 that is coming in from the network cloud (internet) to the same port on the linux box. You will also want to forward any established and/or related connections in the same manner.