There were some things missing from the instructions and they were
needlessly complicated, so I made my own.  This is how I setup a
32 bit chroot jail in ubuntu (intrepid specifically).

There are exactly three times in these instructions where the distribution
being used (intrepid) is mentioned.  To use a different (possibly newer version,
or a debian version) change those three places to the next distribution codename.
For the next version of ubuntu replace all instances (3) of intrepid with jaunty.

To install proprietary codecs use the following lines:

su
echo "## Medibuntu
## Please report any bug on https://bugs.launchpad.net/medibuntu/
deb http://packages.medibuntu.org/ intrepid free non-free
deb-src http://packages.medibuntu.org/ intrepid free non-free" >> /etc/apt/sources.list
aptitude update
aptitude install medibuntu-keyring
aptitude update
aptitude install w64codecs # for AMD64 systems
aptitude install w32codecs # for 32 bit i386 systems


To install the 32 bit chroot jail use the following:

cd /
su
aptitude install schroot debootstrap
mkdir /chroot/
cd /chroot
debootstrap --arch=i386 intrepid /chroot http://us.archive.ubuntu.com/ubuntu
unalias cp
cp /var/lib/locales/supported.d/* /chroot/var/lib/locales/supported.d/
cp -f /etc/apt/sources.list /chroot/etc/apt/
cp -f /etc/passwd /chroot/etc/
cp -f /etc/shadow /chroot/etc/
cp -f /etc/group /chroot/etc/
cp -f /etc/sudoers /chroot/etc/
cp -f /etc/hosts /chroot/etc/
echo "##chroot
/home  /chroot/home       none    rbind  0  0
/dev   /chroot/dev        none    rbind  0  0
/etc   /chroot/etc/.root  none    bind   0  0
/proc  /chroot/proc       none    rbind  0  0
/media /chroot/media      none    rbind  0  0
/mnt   /chroot/mnt        none    rbind  0  0
/tmp   /chroot/tmp        none    rbind  0  0" >> /etc/fstab
mkdir /chroot/etc/.root
mount -a
chroot /chroot
  dpkg-reconfigure locales
  apt-get update
  apt-get upgrade
  apt-get install aptitude mplayer firefox
  apt-get install w32codecs flashplugin-nonfree

  # ...

exit