I understand about cutting edges and all that, but could you offer some hints? I tried building 2.3.40 with the kernel PCMCIA support enabled. That appeared to work but attempts to insmod the 3c589_cs.o module produced a complaint about being unable to allocate the IRQ. That was with cardmgr active. With cardmgr not active, the card wasn't activated, as far as I can tell. The reason I'm trying to use 2.3.40 isn't the new PCMCIA stuff, and I'm no wizard (especially not in that area) so I don't know where to start.
Tried to build the full 3.1.9 pcmcia package; that got a compile error in wireless/airo_cs.c. But skipping that directory, while it produced a build that completed, didn't result in working PCMCIA Ethernet.