This happens when building admincd-stage1 from scratch with catalyst: configure: error: sys/capability.h header is required for Linux capabilities support. Either install libcap or use --disable-linux-caps. Workaround is to comment it out from the spec file, and some other package eventually pulls it in, after which the build succeeds. Desired solution would be to either add sys-libs/libcap as a hard dependency, or add a "caps" USE flag similar to the net-misc/iputils package, which would add --disable-linux-caps configure option for net-dns/bind-tools.
Sorry if the original report is unclear, sys/capability.h, provided by sys-libs/libcap, is required for building net-dns/bind-tools in its current configuration. Normally libcap gets pulled in by system packages such as glibc if USE=caps is enabled. But when building stage1 with catalyst, libcap is emerged after bind-tools and so the initial build fails. Therefore the ebuild for bind-tools should have libcap as dependency if "caps" is enabled, or add --disable-linux-caps to bind-tools ./configure arguments if "caps" is not enabled.
*** This bug has been marked as a duplicate of bug 691712 ***
