Hmmm... It depends on how you connect It. If you are able to mimic the gayle's pcmcia interface, yes, you can use standard drivers.
I was thinking more that the existing drivers could be modified to support your new interface. My Prism-II wireless driver for example is open source, and the code is modular with regard to buses: internally, there are modules for PCMCIA, PCI etc. You would just need to add a small "A500" module; the core wireless chipset driver would stay the same.