[boost] [test] Any dependency on Boost.Test requires C++11 ?

At present any test in Boost.Math that depends on Boost.Test fails for GCC prior to 4.5 because the build script for Boost.Test has: <toolset>gcc:<cxxflags>-std=gnu++0x Is this really required? It looks wrong headed to me: * We already have testers that test both C++03 and C++11 modes - so we don't need this to test C++11 support. * It's presence makes testing gcc in C++03 mode impossible if the library uses Boost.Test - so there may be C++03 breakages that we don't know about because of this. * As mentioned above, this is a hard error for GCC prior to 4.5, so those compilers can't be tested either. Can this be safely removed? Many thanks, John.