Thanks, I'll try to check the modem, if it is possible to configure it. It was supplied by NTL. Yes the forwarding is setup on the airport, I'll try the 5988 too
The problem is quite easy to explain, but I haven't found a solution yet.
The following are the hardware/ software I have.
In my home
PowerMac G5
OS X 10.4.10
Apple Remote Desktop 3.1
At Uni
Ibook G4
OS X 10.4.10
Apple Remote Desktop 3.1
Internet connection at home
Cable modem (NTL/Virgin)...