alternatively, if you don't want to install the firewall, all you have to do is put the following line of text (use notepad) at the bottom of your hosts file (c:\windows\hosts, or c:\winnt\system32\drivers\etc\hosts):

127.0.0.1 www.xolox.nl
127.0.0.1 xolox.nl

you can probably use a bogus IP address too, but that works for me.