Index: detail/config.hpp
===================================================================
--- detail/config.hpp	(revision 40426)
+++ detail/config.hpp	(working copy)
@@ -62,7 +62,7 @@
 
 //____________________________________________________________________________//
 
-#ifdef __GNUC__
+#if defined (__GNUC__) || defined(_MSC_VER)
 #define BOOST_TEST_PROTECTED_VIRTUAL virtual
 #else
 #define BOOST_TEST_PROTECTED_VIRTUAL
