/usr/lib/gcc/x86_64-linux-gnu/4.6.1 is a symlink to /usr/lib/gcc/x86_64-linux-gnu/4.6. I assume you did mess it up with you "work arounds". just apt-get remove cpp-4.6, and rm -rf /usr/lib/gcc/x86_64-linux-gnu, and re-install
/usr/lib/ gcc/x86_ 64-linux- gnu/4.6. 1 is a symlink to /usr/lib/ gcc/x86_ 64-linux- gnu/4.6. I assume you did mess it up with you "work arounds". just apt-get remove cpp-4.6, and rm -rf /usr/lib/ gcc/x86_ 64-linux- gnu, and re-install