If you have x11 removed from DISTRO_FEATURES but include zypper in your image, the build will fail as libzypp now DEPENDS on libproxy, which DEPENDS on gconf, which DEPENDS on gtk+, which cannot build without x11 or directfb.
http://git.yoctoproject.org/cgit.cgi/poky/commit/?id=5b78c7d559dd96b414727b85205958bd3f2ece2e