By wan side you mean using the public ip address? ive tried that...
ive used WAN IP 192.168.2.101, public ip, LAN IP...
router is Linksys RVS4000, fw V1.1.09
edit: Also, when i do use the WAN IP, it just continues to diplay "Connecting to Server" unless i kill the process.
As when i tried the others it said cant connect.
EDIT 2: I fixed it! thanks gamba. it was the Wan ip that i needed, also i needed to use the default 4550 and open that port on the router. some stupid guide told me to use 3550 no matter what the default was...