The sample program at http://en.highscore.de/cpp/boost/src/3.4.3/main.cpp can't be compiled anymore with Boost 1.46.1 (using VC++ 2010). Is this a known problem? 1>------ Rebuild All started: Project: Test, Configuration: Debug Win32 ------ 1> main.cpp 1>c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(539): error C2668: 'boost::mem_fn' : ambiguous call to overloaded function 1> c:\boost\include\boost-1_46_1\boost\bind\mem_fn_cc.hpp(25): could be 'boost::_mfi::mf1<R,T,A1> boost::mem_fn<void,world,std::ostream&>(R (__thiscall world::* )(A1))' 1> with 1> [ 1> R=void, 1> T=world, 1> A1=std::ostream & 1> ] 1> c:\program files (x86)\microsoft visual studio 10.0\vc\include\xxmem_fn(32): or 'std::tr1::_Mem_fn2<_Rx,_Pmf,_Arg0,_Arg1> std::tr1::mem_fn<void,world,std::ostream&>(_Rx (__thiscall world::* )(_Arg1))' [found using argument-dependent lookup] 1> with 1> [ 1> _Rx=void, 1> _Pmf=void (__thiscall world::* )(std::ostream &), 1> _Arg0=world, 1> _Arg1=std::ostream & 1> ] 1> while trying to match the argument list '(void (__thiscall world::* )(std::ostream &))' 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(492) : see reference to function template instantiation 'bool boost::detail::function::basic_vtable2<R,T0,T1>::assign_to<F>(MemberPtr,boost::detail::function::function_buffer &,boost::detail::function::member_ptr_tag)' being compiled 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> &, 1> F=void (__thiscall world::* )(std::ostream &), 1> MemberPtr=void (__thiscall world::* )(std::ostream &) 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(915) : see reference to function template instantiation 'bool boost::detail::function::basic_vtable2<R,T0,T1>::assign_to<Functor>(F,boost::detail::function::function_buffer &)' being compiled 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> &, 1> Functor=void (__thiscall world::* )(std::ostream &), 1> F=void (__thiscall world::* )(std::ostream &) 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(722) : see reference to function template instantiation 'void boost::function2<R,T0,T1>::assign_to<Functor>(Functor)' being compiled 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> &, 1> Functor=void (__thiscall world::* )(std::ostream &) 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(1065) : see reference to function template instantiation 'boost::function2<R,T0,T1>::function2<void(__thiscall world::* )(std::ostream &)>(Functor,int)' being compiled 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> &, 1> Functor=void (__thiscall world::* )(std::ostream &) 1> ] 1> c:\users\boris\documents\visual studio 2010\projects\test\main.cpp(14) : see reference to function template instantiation 'boost::function<Signature>::function<void(__thiscall world::* )(std::ostream &)>(Functor,int)' being compiled 1> with 1> [ 1> Signature=void (world *,std::ostream &), 1> Functor=void (__thiscall world::* )(std::ostream &) 1> ] 1>c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(539): error C2780: 'bool boost::detail::function::basic_vtable2<R,T0,T1>::assign_to(const boost::reference_wrapper<FunctionObj> &,boost::detail::function::function_buffer &,boost::detail::function::function_obj_ref_tag)' : expects 3 arguments - 2 provided 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(625) : see declaration of 'boost::detail::function::basic_vtable2<R,T0,T1>::assign_to' 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1>c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(539): error C2780: 'bool boost::detail::function::basic_vtable2<R,T0,T1>::assign_to(FunctionObj,boost::detail::function::function_buffer &,boost::detail::function::function_obj_tag)' : expects 3 arguments - 2 provided 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(599) : see declaration of 'boost::detail::function::basic_vtable2<R,T0,T1>::assign_to' 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1>c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(539): error C2780: 'bool boost::detail::function::basic_vtable2<R,T0,T1>::assign_to(MemberPtr,boost::detail::function::function_buffer &,boost::detail::function::member_ptr_tag)' : expects 3 arguments - 2 provided 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(533) : see declaration of 'boost::detail::function::basic_vtable2<R,T0,T1>::assign_to' 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1>c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(539): error C2780: 'bool boost::detail::function::basic_vtable2<R,T0,T1>::assign_to(FunctionPtr,boost::detail::function::function_buffer &,boost::detail::function::function_ptr_tag)' : expects 3 arguments - 2 provided 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(511) : see declaration of 'boost::detail::function::basic_vtable2<R,T0,T1>::assign_to' 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] ========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ========== Boris