After emerging xfree-4.3.99.902, many shared objects went to /usr/X11R6/lib64. Neither the ebuild not env-update added this path to /etc/ld.so.conf, so I had to do it manually. Without this step, xfree doesn't start.
this has been fixed.... 4.3.99.902 wasn't even keyworded for amd64 when you tried this. Resync your tree and try it again ... please don't report bugs on stuff not working that hasn't been keyworded, it just clutters up bugs.gentoo.org, and is counter-productive for us.