Compilation fix for Boost 1.49
Compilation fix for Boost 1.49

BlueBrain/flatbuffers,rdumusc/flatbuffers,rdumusc/flatbuffers,rdumusc/flatbuffers,BlueBrain/flatbuffers,BlueBrain/flatbuffers,BlueBrain/flatbuffers,rdumusc/flatbuffers,BlueBrain/flatbuffers,rdumusc/flatbuffers,BlueBrain/flatbuffers,rdumusc/flatbuffers