Hosted games not getting past router.

Hi all. Can anyone help me??? I have recently started using a netgear wireless router and adaptor and i seem to be having problems hosting internet games.
When i launch a game to the net it starts no problems but when i and others try to find it on the game servers it does not show up in the list. BUT when i look for it on LAN games there it is, even though i have not launched a LAN game. It appears that the game is not getting past my router. Do i need to configure something in the router settings to allow.
P.S. The game is AvP2 and I can join internet games no problem.
Please Please someone help.
Slackrabbit