Hi Tiago, thanks for the quick fix. I've been able to configure and build it successfully. the import now works but I get the same interpreter mismatch error as before. I'm using homebrew for building both python, cgal, graphviz, boost, numpy and scipy and they are all built with apple gcc 4.2 and linked to the homebrewed python in /usr/local/. Here's the error by the interpreter: Fatal Python error: Interpreter not initialized (version mismatch?) Abort trap: 6 I've checked for the configure output of graph_tool, and there's something which it might be creating problems: [..] checking for python... /usr/local/bin/python checking for a version of Python >= '2.1.0'... yes checking for a version of Python 2.5... yes checking for the distutils Python package... yes checking for Python include path... -I/usr/local/Cellar/python/2.7.2/Frameworks/Python.framework/Versions/2.7/include/python2.7 checking for Python library path... -L/usr/local/Cellar/python/2.7.2/Frameworks/Python.framework/Versions/2.7/lib/python2.7 -lpython2.7 checking for Python site-packages path... /usr/local/Cellar/python/2.7.2/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages checking python extra libraries... -ldl -framework CoreFoundation checking python extra linking flags... -u _PyMac_Error Python.framework/Versions/2.7/Python checking consistency of all components of python development environment... yes checking for python build information... checking for python2.7... python2.7 checking for main in -lpython2.7... yes checking python2.7/Python.h usability... yes checking python2.7/Python.h presence... yes checking for python2.7/Python.h... yes results of the Python check: Binary: python2.7 Library: python2.7 Include Dir: /Developer/SDKs/MacOSX10.7.sdk/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 checking whether python version >= 2.5... yes checking for python version... 2.7 checking for python platform... darwin checking for python script directory... ${prefix}/lib/python2.7/site-packages checking for python extension module directory... ${exec_prefix}/lib/python2.7/site-packages checking for boostlib >= 1.38.0... yes checking whether the Boost::Python library is available... yes checking for exit in -lboost_python... no checking for exit in -lboost_python... (cached) no checking for exit in -lboost_python-mt... yes checking whether the Boost::Iostreams library is available... yes checking for exit in -lboost_iostreams... no checking for exit in -lboost_iostreams... (cached) no checking for exit in -lboost_iostreams-mt... yes checking whether the Boost::Regex library is available... yes checking for exit in -lboost_regex... no checking for exit in -lboost_regex... (cached) no checking for exit in -lboost_regex-mt... yes checking whether the Boost::Graph library is available... yes checking for exit in -lboost_graph... no checking for exit in -lboost_graph... (cached) no checking for exit in -lboost_graph-mt... yes checking for main in -lCGAL... yes checking python2.7 module: numpy... yes checking for /usr/local/Cellar/python/2.7.2/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/numpy/core/include/numpy/arrayobject.h... yes checking python2.7 module: scipy... yes checking /usr/local/Cellar/python/2.7.2/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/scipy/weave/scxx/object.h usability... yes checking /usr/local/Cellar/python/2.7.2/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/scipy/weave/scxx/object.h presence... yes checking for /usr/local/Cellar/python/2.7.2/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/scipy/weave/scxx/object.h… yes For what I can see the python libs are correctly found in /usr/local/ except for these lines: checking for python2.7/Python.h... yes results of the Python check: Binary: python2.7 Library: python2.7 Include Dir: /Developer/SDKs/MacOSX10.7.sdk/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 where apparently the original Xcode python is found. why's that? do you have any suggestions on configure options for it to stick it to the correct versions? i've tried some options based on python-config but unsuccessfully. By looking at the way graph_tool is built, i don't really get what's going on, because both -I and -L options are /usr/local/ paths. I attach here the config.log, hoping it can help.