Weirdly, as I'm sure you've found, PB don't list the MX37 on their support downloads site. They do mention the MX52, though, which I see also has an Atheros wireless LAN driver. Have you tried that? It's for Vista.
I just thought. What makes you say the driver isn't working? Is there a yellow exclamation mark against it in Device Manager? Or are saying it must be the driver not working, because you can't make a wifi connection?