Netopia 6.3 Software User's Manual page 51

Note the following parameters for the "my-games" Pinhole:
1. The Protocol ID is UDP.
2. The external port is specified as a range.
3. The Internal port is specified as the lower range entry.
REMEMBER: When you have re-assigned the port address for the
embedded Web server, you can still access this facility.
Use the Gateway's WAN address plus the new port number.
In this example it would be
<WAN Gateway address>:<new port number> or, in this case,
210.219.41.20:8100