WARNING: couldn't open cd9660 (after loading kernel, before loading ramdisk), or: how do I put a file-system into the kernel (not as module)

[Hubert Feyrer <hubert%feyrer.de@localhost>]

I'm toying with -current, and wonder what the following error when booting 
from an ISO means (i386):

        > load miniroot.kmod
        > boot
        6122760+454896+292596 [370528+368073]=0x743260
====>        WARNING: couldn't open cd9660 
(/stand/i386/5.99.56/modules/cd9660/cd9660.kmod)
        Loading miniroot.kmod
        WARNING: 1 module failed to load
        Copyright (c) 1996, 1997, ...
        <regular kernel startup, then boot into miniroot>

I have trouble that -current doesn't read my boot.cfg at all (read returns 
0 bytes; the ISO seems to have to right file as indicated by some debug 
printfs. I don't understand why the kernel (or who?) wants to load 
cd9660.kmod.

Is there a way to build the CD9660 file-system into the kernel, but 
keeping the rest modular (or at least loading the ramdisk)?
How does one hardwire modules into the kernel in -current kernel configs?


 - Hubert