Pardus fellow craft
I've been working with virtualbox yesterday on SuSE and had the same problem. It can be fixed by installing the guest addons on the virtualized XP. Just boot the virtual pc and then click the device > Install guest addons option when XP is fully booted. If I'm correct you should then get a setup window to install those. If it still doesn't work go to the hardware listing dialog (just rightclick this computer > properties and I believe it was somewhere in the second or third tab, in dutch it's called apparaatbeheer). Then find the ethernet card and if it's not functioning (it has a question mark symbol over the card icon) you will have to install the drivers yourself. If that is the case doubleclick the card, then take the second tab and click the install driver button. Then go to the cd player (in your virtual pc that is) and go to the AMD_PC (or some similar named folder) and choose the inf file there. It will install the drivers and then you should be able to use the network adapter, just configure the internet settings.