I installed FC4 on one of two harddrives (the other has XP).
This distro works fine but I need a 2.4 kernel running because the SDK I will be using requires kernel 2.4.

So I can compile (after several patches) 2.4.31 but when the kernel loads its states
that it cannot not find "init". I used "make install" and it creates /tmp/initrd.img.xxxx. with an error stating that "Permission denied". But I tried to use it anyway.

My grub.conf now looks like:

default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Fedora Core (2.6.11-1.1369_FC4)
root (hd0,0)
kernel /vmlinuz-2.6.11-1.1369_FC4 ro root=/dev/VolGroup00/LogVol00 rhgb quiet
initrd /initrd-2.6.11-1.1369_FC4.img
title Fedora Core 2.4.31
root(hd0,0)
kernel /bzImage root=/dev/hdc1
initrd /initrd.img.q10481

I tried changing "/dev/hdc1" to "/dev/VolGroup00/LogVol00 rhgb quiet" but that
made matters worse.

I was guess it had something to do with the make menuconfig.
Enabling ext3 journel does help.
I disabled Module support because that caused many compile errors.

If anybody has a solution for kernel 2.4 on FC4 it would be appreciated.

at the very least you need the old style modutils to go with that
i'm kind of wondering if this is possible at all because of udev and stuff
but i guess you could disable udev if you need to and run an old /dev devices script
to permanently populate /dev if udev won't work

I did try it with modutils-2.4.22. I got the same issue and in addition it broke the loading of the 2.6 kernel that came with the distro. I guess something in modutils is used during runtime of the kernel.
Intalling module-init-tool-3.1 solved that problem. But am still stuck with original problem.

From the general sound of things, if I want kernel 2.4, I should use FC3 or RH9?