Some VS 6.0 compatibility fixes from Hirokazu Yamamoto which are also useful for later versions of MSVC. VS6 claims that fortran is a reserved word
diff --git a/Modules/errnomodule.c b/Modules/errnomodule.c
index b1beb00..ab4b5f1 100644
--- a/Modules/errnomodule.c
+++ b/Modules/errnomodule.c
@@ -5,6 +5,7 @@
 
 /* Windows socket errors (WSA*)  */
 #ifdef MS_WINDOWS
+#define WIN32_LEAN_AND_MEAN
 #include <winsock.h>
 #endif