These ebuilds come from http://git.overlays.gentoo.org/gitweb/?p=user/klondike.git;a=summary.
If you have some problems, go to the official site first.
libclc : OpenCL C library ( http://libclc.llvm.org/ )
opensc : Libraries and applications to access smartcards ( http://www.opensc-project.org/opensc/ )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a klondike
For Paludis use this rsync : rsync://gentoo.zugaina.org/klondike-portage
If you have a problem : ycarus(-at-)zugaina.org