> if its only mechanical similar, but not electronically compatible > with PCMCIA cards, why are people still asking about PCMCIA > drivers for G4 Powermacs
Because the only electrical difference are some pins that Apple permuted on purpose. Of course, that small hardware change would require a small change to the existing driver:
"The driver would need to be modified first, but it wouldn't be huge job. The original Airport card uses a Prism-II chipset too." http://www.amiga.org/forums/showpost.php?p=623976
Technically you're correct though. The small hardware change Apple applied effectively renders AirPort non-PCMCIA.