When running emerge with the '-b' flag, it errors out with the following (otherwise, using '--buildpkg' works fine): emerge: error: option -b: invalid choice: '--buildpkg' (choose from 'True', 'n') I believe that (the Git) commit 6619072006bd7 is responsible for this.
Thanks, this is fixed in git: http://git.overlays.gentoo.org/gitweb/?p=proj/portage.git;a=commit;h=d196314b88833b27ee95aa29ebd3df20d7dc1df5
This is fixed in 2.2_rc93.