diff --git a/src/ImplPtr.h b/src/ImplPtr.h
index be1cea9..fb0c43c 100644
--- a/src/ImplPtr.h
+++ b/src/ImplPtr.h
@@ -25,6 +25,9 @@
 #ifndef ImplPtr_h
 #define ImplPtr_h
 
+//#include <boost/config/select_compiler_config.hpp>
+#define BOOST_NO_CXX11_EXPLICIT_CONVERSION_OPERATORS
+
 #include <boost/noncopyable.hpp>
 #include <boost/scoped_ptr.hpp>