[boost] [mpi] BOOST_HAS_LONG_LONG but no is_mpi_datatype<long long>

I'm trying to send a class with a uint64_t member and although my compiler (gcc 4.0.2), MPI library (OpenMPI 1.2.5) and boost library (SVN branches/release) all support "long long" natively on 32-bit i386, I noticed the necessary code is "#if 0" undefined in boost/mpi/datatype.hpp Just wondering why? #if 0 #ifndef BOOST_NO_INTRINSIC_WCHAR_T BOOST_MPI_DATATYPE(wchar_t, MPI_WCHAR, builtin); #endif #ifdef BOOST_HAS_LONG_LONG BOOST_MPI_DATATYPE(long long, MPI_LONG_LONG_INT, builtin); BOOST_MPI_DATATYPE(unsigned long long, MPI_UNSIGNED_LONG_LONG, builtin); #endif #endif Cheers, Simon