The oldest version available from upstream at http://www.cpan.org/authors/id/B/BI/BINGOS/ is 2.88 so any version in portage below 2.940.0 can't be fetched anymore. The recently stabilised version 2.840.0 (#458122) is therefore not installable. # ebuild $(equery w perl-core/Module-CoreList) fetch >>> Downloading 'http://de-mirror.org/distro/gentoo/distfiles/Module-CoreList-2.84.tar.gz' --2013-11-28 12:12:43-- http://de-mirror.org/distro/gentoo/distfiles/Module-CoreList-2.84.tar.gz Resolving de-mirror.org... 195.20.242.90, 2001:8d8:580:400::c314:f25a Connecting to de-mirror.org|195.20.242.90|:80... connected. HTTP request sent, awaiting response... 404 Not Found 2013-11-28 12:12:43 ERROR 404: Not Found. >>> Downloading 'http://www.cpan.org/authors/id/B/BI/BINGOS/Module-CoreList-2.84.tar.gz' --2013-11-28 12:12:43-- http://www.cpan.org/authors/id/B/BI/BINGOS/Module-CoreList-2.84.tar.gz Resolving www.cpan.org... 212.117.177.118, 2a01:608:2:4::2, 2620:101:d000:8::140:1 Connecting to www.cpan.org|212.117.177.118|:80... connected. HTTP request sent, awaiting response... 404 Not Found 2013-11-28 12:12:44 ERROR 404: Not Found. >>> Downloading 'http://search.cpan.org/CPAN/authors/id/B/BI/BINGOS/Module-CoreList-2.84.tar.gz' --2013-11-28 12:12:44-- http://search.cpan.org/CPAN/authors/id/B/BI/BINGOS/Module-CoreList-2.84.tar.gz Resolving search.cpan.org... 199.15.176.161 Connecting to search.cpan.org|199.15.176.161|:80... connected. HTTP request sent, awaiting response... 302 Found Location: http://www.cpan.org/authors/id/B/BI/BINGOS/Module-CoreList-2.84.tar.gz [following] --2013-11-28 12:12:44-- http://www.cpan.org/authors/id/B/BI/BINGOS/Module-CoreList-2.84.tar.gz Resolving www.cpan.org... 212.117.177.118, 2620:101:d000:8::140:1, 2a01:608:2:4::2 Connecting to www.cpan.org|212.117.177.118|:80... connected. HTTP request sent, awaiting response... 404 Not Found 2013-11-28 12:12:44 ERROR 404: Not Found. !!! Couldn't download 'Module-CoreList-2.84.tar.gz'. Aborting.
Problem is in your mirror settings. http://de-mirror.org/distro/gentoo returns 404, though http://de-mirror.org/gentoo/distfiles/Module-CoreList-2.84.tar.gz works fine.