Remastersys

Add to /etc/apt/source.list

deb http://www.geekconnection.org/remastersys/repository karmic/

Install remastersys

apt-get update
apt-get install -y --force-yes remastersys

--force-yes allows to install remastersys without gpg signature

This will also install:

casper discover1 discover1-data dmsetup libdebconfclient0
libdebian-installer4 libdiscover1 localechooser-data mtools
os-prober remastersys squashfs-tools syslinux user-setup
ubiquity ubiquity-casper ubiquity-frontend-gtk ubiquity-ubuntu-artwork