Trying to start debian netinstall from .iso on booted CD/DVD

[<arcarlini@iee.org>]

I'm trying to build a DVD with multiple distributions and live CDs on
it.

I want to add Debian to that but I'm having some problems.

I don't have that much room left so I'm starting from the netinstall
and
I'll then rely on being able to pickup whatever else I want over the
net.

My first attempt was to copy the netinstall contents into a /debian
subdirectory and then invoke that through islinux.cfg. After some
fiddling I got that to start up but it eventually failed when the
installer decided that my distribution was corrupt.

Fair enoug, I have fiddled with it, so it's not surprising that
stuff isn't where it expects to find it.

So I decided to try a different tack. This page:
  http://d-i.pascal.at/
describes how to install a debian ISO from a USB stick.

I grabbed the necessary files and tried the idea out on my DVD.
Sadly it doesn't work. Again the installer starts up and asks a
few questions but soon decideds that it cannot find the .iso file.
When I drop to a shell and have a look there is no sign of the
CDROM.

So now I'm a little stuck. Can anyone suggest how I can achieve my
objective
of dropping a netinstall.iso onto my DVD, booting my DVD and having
that
Install happen from the ISO?

Thanks

Antonio
arcarlini@iee.org