initrd-kickseed cannot find kickstart file although it is there

[Graham Bucknell]

I am trying to build a new Ubuntu 10.04.1 vm using kickstart . I've made a custom boot cd based on the mini.iso here: (http://archive.ubuntu.com/ubuntu/dists/lucid/main/installer-i386/current/images/netboot/mini.iso)

Then have made a simple kickstart file based on the hostname of the machine and pointed to it in isolinux.cfg :

default autoinstall
label autoinstall
menu label ^Automatically Install Ubuntu
kernel linux
append file=/cdrom/preseed/ubuntu.seed initrd=initrd.gz ks=cdrom:/ubuntu32211.cfg

However the installer does not find the kickstart and this message flashes up at boot.

 /lib/kickseed/initrd-kickseed : line 133 can't open /cdrom/ubuntu32211.cfg no such file

It then hits the regular language selection page, as if it has not found the kickstart at all.

The kickstart is there on the cd, and it has obviously found the preseed file correctly. The "ks=cdrom:/path-to-kickstart.cfg" line is the documented syntax. I'll upload logs and the iso I'm using.
Thanks!