Posting for future reference, a solution I found was to install g++-multilib. I had the same incompatible problem relating to -lstdc++ on g++ version 4.6.1
On further probing: g++-multilib is a dummy package which installed g++4.6-multilib which in turn installed the appropriate libstdc++.so under the /usr/lib/gcc/x86_64-linux-gnu/4.6/32 folder.