How do I activate trackpad mouse clicking in Windows?

[luminosity]

I've successfully installed XP using Boot Camp, but now I need to figure out how to use the trackpad's clicking feature in XP. It's a major part of my computer use, and I need it in XP to be able to use it (as a mouse isn't really something I can use).

So, can anyone direct me to how I turn it on?

Edit: I see now that it's not possible, so my apologies for starting this thread.