How to rebind a modified initrd.bz2 into the ElTorito image?

Hello,

I'am working under Linux Mandrake 9.0 with tomsrtbt-2.0.103.
For boot-image testing I use VMware.

I found the tomsrtbt-2.0.103.ElTorito.288.img file on your server and
with a
mkisofs -o toms.iso -b tomsrtbt-2.0.103.ElTorito.288.img -r /data/
I received an well working bootable ISO-Image for linux.

Then I tempted to do some minor changes to the root-fs of
tomsrtbt (initrd.bz2), mounting it via a loopback device.

After builing the ISO again, I made another boot test via VMware
but now received the following error output during the Partition Check.

Partition check:
 sda: unknown partion table
RAMDISK: Couldn't find valid RAM disk image starting at 0.
NTFS version 00607
[MS-DOS FS Rel. 12,FAT 0,check=n,conv=b,uid=0,gid=0,umask=022,bmap]
[me=0x0,cs=0,#f=0,fl=0,ds=0,de=0,data=0,se=0,ts=0,ls=0,rc=0,fc=4294967295]
Transaction block size = 512
[MS-DOS FS Rel. 12,FAT 0,check=n,conv=b,uid=0,gid=0,umask=022,bmap]
[me=0x0,cs=0,#f=0,fl=0,ds=0,de=0,data=0,se=0,ts=0,ls=0,rc=0,fc=4294967295]
Transaction block size = 512
Kernel panic: VFS: Unable to mount root fs on 01:00

The Next thing I tempted to do was to use the unpack.s and 
buildit.s tools from your distribution
(I don't realized them before.)

Unfortunately I had (and have) some difficulties with these tools,
particularly with regard to the ElTorito image.

Now my questions:
Is there an easy way to rebind a modfied initrd.bz2 into the ElTorito
image?

(I take a look at buildit.s and I understand that I have to call lilo
and that I have to tell the kernel where to find the root-fs,
but even so I'am not very familiar with creating booting images, also
I'am not very familiar with ash and lua ...)

Or should I try to bring unpack.s and buildit.s to work on my system?
I have some difficulties with these tools, but I will mail this (maybe)
separately to keep the things clear.

Also I found this:
http://not.toms.net/tomsrtbt/2501/msg02686.html
Is this still current?


best regards
oliver