Steps I followed:
1) Create disk image with Gentoo 2005.0 provided by Linode.
2) Boot this obsolete system
3) Tune some things like:
# rc-update -d keymaps boot
# rc-update -d consolefont boot
# echo HOSTNAME="myhost" > /etc/conf.d/hostname
In make.conf, ensure a properly USE with thinks like -X -gtk -gtk2 etc...
4) Update portage tree: #emerge --sync (fails as your linode, no problem)
5) Upgrade portage: # emerge -u portage
6) rm /etc/make.profile
7) ln -s /usr/portage/profiles/default-linux/x86/2006.1

Sync again: emerge --sync
If you want a perfectly upgraded system...
9) #emerge gcc (take a long long time...)
Then, select your new compiler gcc-4.1.1 as your default compiler if you want it, with gcc-config (depracated but, eselect compiler isn't installed yet

).
Finally, rebuild all the packages with "emerge -e world".
At this point, you're running a Gentoo 2006.1.
Install everything, try kernels 2.6 etc... Enjoy!