During the `emerge -e system' step an attempt is made to emerge man-pages-2.67. This fails because the 2.67 version cannot be downloaded. Perhaps version 2.67 is simply too old.
Looks like it, can you try the 20071213 tree image instead? (Change in bootstrap_tree() of bootstrap-prefix.sh.)
Good news: With the 20071213 tree image man-pages is emerged successfully (it seems I am getting man-pages-2.70).
I committed this, so I consider this fixed by using a more recent snapshot. When an ebuild gets removed in the gentoo-x86 tree, its associated distfiles are also removed from the mirrors. The result is something like this bug, if we are behind. Snapshots easily grow old of course. Let me know if this newer snapshot works, it has only been tested for AIX.