problem with bootstrap-prefix

[lovejoy]

try to install http://www.gentoo.org/proj/en/gentoo-alt/prefix/bootstrap.xml on Red Hat Enterprise Linux AS release 4 (Nahant Update 4)
$ ./bootstrap-prefix.sh $EPREFIX stage3
* Bootstrapping Gentoo prefixed portage installation using
* host: x86_64-pc-linux-gnu
* prefix: /home/lovejoy/Gentoo
* ready to bootstrap stage3

!!! Your current profile is deprecated and not supported anymore.
!!! Use eselect profile to update your profile.
!!! Please upgrade to the following profile if possible:

default/linux/amd64/13.0/no-multilib

You may use the following command to upgrade:

eselect profile set default/linux/amd64/13.0/no-multilib

!!! '(sys-apps/sed' is not a valid package atom.
!!! Please check ebuild(5) for full details.

found same problem http://stackoverflow.com/questions/19005229/sys-apps-sed-is-not-a-valid-package-atom-when-install-gentoo-prefix
any solutions ?