yes, it is possible, i have a wireless connection, and i follow these steps
1) go into your command prompt
(START > All programs > accessories > command prompt)
2) when your in the command prompt, type in IPconfig and press enter
3) it'll tell you your IP, and default gateway
4) open up internet explorer and type in your default gateway
5a) if your Router has a password, type it in and click ok
5b) OR if your taken to a page with something that has your router settings, click Login and if you have a password, type it in and press submit
6) go to "Virtual servers" once your logged in
7) type this infromation in the first secton of the chart:
5029 - 5029 - UPD - (YOUR LAST NUMBER OF YOUR IP ADDRESS HERE, most likey a 1 or a 2) - 5029 - 5029
(and click the check box that says: Enabled)
8) go to the bottom of the page and press submit
Congradulations! you can now netgame with people!