Last month I wrote

Just for the heck of it, I installed NetBSD 1.6 on an old laptop. ... . I've looked around, but I don't see any way to configure what happens during [PCMCIA] card ejection and insertion events. Am I missing something? Do the other BSD variants handle PCMCIA differently?

Well, just for the heck of it, I installed FreeBSD 4.7. It does have a system to handle PCMCIA events; see the man pages for pccardd and pccardc. It correctly handled my network card right out of the box.