[boost] [1.43][beta] Fix for MPL under gcc 4.5

Can : https://svn.boost.org/trac/boost/ticket/4061 be fixed by merging the attached trivial patch ? gcc 4.5 borks up on a deep MPL internals that prevent some other component to not compile. Thanks -- ___________________________________________ Joel Falcou - Assistant Professor PARALL Team - LRI - Universite Paris Sud XI Tel : (+33)1 69 15 66 35