diff --git a/include/libtorrent/session.hpp b/include/libtorrent/session.hpp
index 6056a619a..3a71bb11c 100644
--- a/include/libtorrent/session.hpp
+++ b/include/libtorrent/session.hpp
@@ -64,6 +64,13 @@ POSSIBILITY OF SUCH DAMAGE.
 #	include <eh.h>
 #endif
 
+#ifdef TORRENT_USE_OPENSSL
+// this is a nasty openssl macro
+#ifdef set_key
+#undef set_key
+#endif
+#endif
+
 namespace libtorrent
 {
 	struct plugin;