I'm having problems building boost 1.40 on 64 bit fedora and am hoping for a well known gotcha so I can avoid figuring this out. I'd just finished building 1.40 on Ubuntu 32 bit, and didn't expect any difficulties, but with: Linux 2.6.30.8-64.fc11.x86_64 #1 SMP Fri Sep 25 04:43:32 EDT 2009 x86_64 x86_64 x86_64 GNU/Linux gcc 4.4 1 ICU_LINK="-L/usr/lib64" EXPAT_INCLUDE=/usr/include EXPAT_LIBPATH=/usr/lib64 PATH=$PATH:/usr/lib64/openmpi/bin and: using mpi ; added to the file: /usr/local/boost_1_40_0/tools/build/v2/user-config.jam N.B. building without mpi doesn't get rid of the problems there's the same number. I get a HUGE amount of errors in the build such as (these are the first two of 90087): gcc.compile.c++ bin.v2/libs/mpi/build/gcc-4.4.1/release/threading-multi/broadcast.o In file included from ./boost/mpi/detail/mpi_datatype_cache.hpp:14, from ./boost/mpi/datatype.hpp:28, from ./boost/mpi/communicator.hpp:21, from ./boost/mpi/collectives.hpp:22, from ./boost/mpi/collectives_fwd.hpp:20, from ./boost/mpi/collectives/broadcast.hpp:12, from libs/mpi/src/broadcast.cpp:10: ../boost/mpi/detail/mpi_datatype_oarchive.hpp: In member function ‘void boost::mpi::detail::mpi_datatype_oarchive::save_enum(const T&, mpl_::true_)’: ../boost/mpi/detail/mpi_datatype_oarchive.hpp:64: error: expected primary-expression before ‘enum’ ../boost/mpi/detail/mpi_datatype_oarchive.hpp:64: error: expected ‘;’ before ‘enum’ Is there any well known gotcha I can fix before I spend the time to figure it out?