How to compile my own kernel?

[Andreas Heider]

Hi,
today i sucessfully installed the new fbsd 7 on my powermac g4. It was
very easy to install and even boots after installing. (I had some
problems with netbsd ;))
But i want to use the mac as a isdn router, i tried netbsd and linux
before, but they had no isdn support for big endian machines. Only the
linux hisax drivers worked a little bit, they dont like the telephone
system here, i had even on x86 problems with them.
So i tried to use the new freebsd isdn drivers
(http://lists.freebsd.org/pipermail/freebsd-isdn/2005-August/000420.html)
, i only added a few things in the configuration,
(http://home.c2i.net/hselasky/isdn4bsd/privat/temporary/155/Makefile
search for help) everything worked except options IPR_VJ, so i deleted
it. Then everything compiled fine, but the kernel doesnt even boot. I
get KDB: debugger backend: ddb
KDB: current backend: ddb
and nothing else.
Is there any chance to get isdn working on bsd? Isdn on netbsd doesnt
even compile, it seems not to work with ppc.

How can i boot my old kernel? And how can i get the new kernel booting?

Thanks,
Andreas Heider