Please add "~amd64" to the KEYWORDS for app-emulation/simh-3.5.0 , it works fine here. emerge info: Portage 2.0.53_rc4 (default-linux/amd64/2005.0, gcc-3.4.4, glibc-2.3.5-r2, 2.6.13-gentoo-r1 x86_64) ================================================================= System uname: 2.6.13-gentoo-r1 x86_64 AMD Athlon(tm) 64 Processor 3500+ Gentoo Base System version 1.12.0_pre8 ccache version 2.4 [disabled] dev-lang/python: 2.2.3-r6, 2.3.5, 2.4.2 sys-apps/sandbox: 1.2.13 sys-devel/autoconf: 2.13, 2.59-r7 sys-devel/automake: 1.4_p6, 1.5, 1.6.3, 1.7.9-r1, 1.8.5-r3, 1.9.6-r1 sys-devel/binutils: 2.16.1 sys-devel/libtool: 1.5.20 virtual/os-headers: 2.6.11-r2 ACCEPT_KEYWORDS="amd64 ~amd64" AUTOCLEAN="yes" CBUILD="x86_64-pc-linux-gnu" CFLAGS="-march=k8 -pipe -O3" CHOST="x86_64-pc-linux-gnu" CONFIG_PROTECT="/etc /usr/kde/2/share/config /usr/kde/3.4/env /usr/kde/3.4/share/config /usr/kde/3.4/shutdown /usr/kde/3/share/config /usr/lib/X11/xkb /usr/lib64/mozilla/defaults/pref /usr/share/config /var/qmail/control" CONFIG_PROTECT_MASK="/etc/gconf /etc/terminfo /etc/texmf/web2c /etc/env.d" CXXFLAGS="-march=k8 -pipe -O3" DISTDIR="/usr/portage/distfiles" FEATURES="autoconfig distlocks sandbox sfperms strict" GENTOO_MIRRORS="http://distfiles.gentoo.org http://distro.ibiblio.org/pub/linux/distributions/gentoo" MAKEOPTS="-j3" PKGDIR="/usr/portage/packages" PORTAGE_TMPDIR="/var/tmp" PORTDIR="/usr/portage" PORTDIR_OVERLAY="/usr/local/portage" SYNC="rsync://rsync.gentoo.org/gentoo-portage" USE="amd64 X Xaw3d a52 aac aalib acl acpi aim alsa apache2 audiofile avi bash-completion berkdb bitmap-fonts bonobo bzip2 bzlib calendar cdr crypt cups curl dga dio dvd eds emacs emboss encode encoder esd ethereal exif fam fftw flac fontserver foomaticdb fortran ftp gd gdbm gif ginac gnome gnutls gphoto2 gpm gstreamer gtk gtk2 gtkhtml guile icq ieee1394 imagemagick imap imlib ipv6 java joystick jpeg lcms lesstif libwww lirc lm_sensors lzw lzw-tiff maildir mikmod mime mmap mng motif mozilla mp3 mpeg msn ncurses nls nptl offensive ogg oggvorbis openal opengl oscar pam pdflib perl plotutils png posix ppds python quicktime readline samba scanner sdl sharedmem sndfile sockets sox speex spell ssl svg sysvipc tcltk tcpd tetex theora tiff truetype truetype-fonts type1-fonts usb userlocales vorbis wmf xine xml xml2 xmms xpm xv xvid yahoo zlib userland_GNU kernel_linux elibc_glibc" Unset: ASFLAGS, CTARGET, LANG, LC_ALL, LDFLAGS, LINGUAS
it works fine ~amd64 keyword added Thanks for the report