> any ideas on what i might be doing wrong ? Actually, you're not doing anything wrong. It's just that the package in question is hard-masked in /usr/portage/profiles/package.mask so you'll have to unmask it in /etc/portage/package.unmask to use it. But take notice of the comment in the mask-file for powershell as there's probably a somewhat good reason for it to be masked.
Patrick Börjesson -- Public key id: 4C5AB0BF Public key available at search.keyserver.net[:11371]
pgp00000.pgp
Description: PGP signature