diff --git a/configure.ac b/configure.ac
index 4de263a..9aa0f69 100644
--- a/configure.ac
+++ b/configure.ac
@@ -200,6 +200,10 @@ esac
 AX_CC_FOR_BUILD
 
 AH_BOTTOM([
+#if defined(__MINGW32__) && !defined(_WIN32_WINNT)
+#define _WIN32_WINNT 0x0600  /* for STARTUPINFOEX */
+#endif
+
 /* Force using of NLS for W32 even if no libintl has been found.  This is
    okay because we have our own gettext implementation for W32.  */
 #if defined(HAVE_W32_SYSTEM) && !defined(ENABLE_NLS)