nbconfig: need at least one "file-system" line

[Eric Haszlakiewicz <erh%swapsimple.com@localhost>]

Is there something special that I need to do to build a GENERIC kernel now?
I haven't been paying much attention to -current, but I just updated and
tried to build one with:

build.sh tools
build.sh kernel=GENERIC

but it failed with a error:
nbconfig: need at least one "file-system" line

Sure enough, all the file-system lines are commented out.  I have a 
feeling this has something to do with modular builds, but I'm not sure 
what to do from here.

eric