Hi,
I don't know if this is the same kind of bug, but with my nebsd-2.0 box
I have the "umass buffer allocation" error quite often, which can be
solved by creating a 100MB file and then removing it.
When I insert my pccard NIC I sometimes have something like:

rtk0: can't allocate recv buffer, error = 12
I can solve the problem by creating a 100MB file and rm'ing it...

Isn't it a more general NetBSD bug about memory allocation ?

Regards.
Fabien Devaux.