g++-mp-4.1 missing after installing gcc41

After installed gcc41, I found that g++-mp-4.1 is missing, and /opt/local/include/gcc41/ does not even exist (but gcc-mp-4.1 seems working, at least it can print out the built-in specs by specifying -v).... Is it supposed to be like this, or is there something wrong there, or is there another package for g++4.1? Thank a lot, Hui