Hi! I've built and installed successfull Python 2.7.1 that I've separately tested for an application with a boost-1.45.0 build that I also installed successfully. But for another application, I needed to build and install boost-1.44.0 and here I also I've been able to build/install boost successfully using the documentation (bootstrap/bjam after specifying prefix and with-python arguments). But when I build the (C++) application which invokes *Py_Init(...)*, I am getting the following error: *Linking CXX executable ../../../myapp_exec ../../../../../config/cmake/platforms/../../../../3rdparty/2012/package/rh5_x86_64_gcc-4.1.2/boost-1.44.0/lib/libboost_python-gcc41-1_44.so: undefined reference to `Py_InitModule4' collect2: ld returned 1 exit status gmake[2]: *** [myapp_exec] Error 1 * I am completely stuck here and would greatly appreciate any ideas to help understand and try to resolve this. I can easily do another boost-1.44.0 build with an older version of python to see if that helps. Thanks in advance for your time and please let me know if you have any questions. Thanks, -Sunil.