diff --git a/src/win32/i_input.cpp b/src/win32/i_input.cpp
index a26ff320e..941fc15de 100644
--- a/src/win32/i_input.cpp
+++ b/src/win32/i_input.cpp
@@ -110,6 +110,11 @@
 #include "rawinput.h"
 
 
+// Compensate for w32api's lack
+#ifndef GET_XBUTTON_WPARAM
+#define GET_XBUTTON_WPARAM(wParam) (HIWORD(wParam))
+#endif
+
 
 #ifdef _DEBUG
 #define INGAME_PRIORITY_CLASS	NORMAL_PRIORITY_CLASS