Remote Desktop Access through NAT

[Ernst]

I´m running a W98 client trying to use Remote Desktop to connect to Windows XP Professional PC´s sharing a DSL connection in a remote location.

I am very familiar with the usage of Remote Desktop, and I can access the main PC and all its functions just fine - but I have not found a way to reach the other 2 PCs. They all share 1 IP address, and I can access the drives of the other 2 PC's from within the Remotely Connected PC, but I cannot access them from the outside using remote desktop.

Is there some port or different domain I can enter in order to access these PCs??