Unable to connect wirelessly to internet with virgin media freedom net

A member of my family has just received their freedom netbook, and asked me to set it up for them. The problem I have is that i am unable to connect to the internet via their wireless connection. I know the wireless is ok, as i connected their other laptop to it a couple of weeks ago.
Do i have to do anything to the netbook, or should it be automatic.
I have started the windows wireless zero configuration utility, and it still doesn't work.
They have a desktop pc with windows 7(connected to router by ethernet), laptop with vista(wireless), and the netbook with windows xp home.
Has anyone had the same problem, and if so, what do you suggest?