Driver signing under 32-bit XP and Vista

Hello everyone.

I've developed a kernel-mode driver for 32-bit XP and Vista.

The proper way is to sign the package now, but I'm just stumbled over the variety of options.

As I understand, to sign my driver package I need a valid certificate. It's possible to buy one, e.g. from VeriSign for 99$.

But prior to buying a certificate, I would like to ask people who did driver signing -- is it necessary to buy a certificate for 32-bit systems, or there's e.g. a way to generate it locally or other legal way to obtain it for free?

Regards,
Evgeny.