Update to require IE 5.1 as it is required to build on mingw64.
@ -43,7 +43,7 @@ namespace boost {
#ifdef _WIN32_IE
#undef _WIN32_IE
#endif
#define _WIN32_IE 0x0400
#define _WIN32_IE 0x0501
#define WIN32_LEAN_AND_MEAN 1
#ifndef NOMINMAX
#define NOMINMAX