diff --git a/freeglut/freeglut/include/GL/freeglut_std.h b/freeglut/freeglut/include/GL/freeglut_std.h
index 5ffc5a0..37d29be 100644
--- a/freeglut/freeglut/include/GL/freeglut_std.h
+++ b/freeglut/freeglut/include/GL/freeglut_std.h
@@ -413,6 +413,9 @@
 
 #define  GLUT_SPACEBALL_BUTTON_A            0x0001
 #define  GLUT_SPACEBALL_BUTTON_B            0x0002
+#define  GLUT_SPACEBALL_BUTTON_C            0x0004
+#define  GLUT_SPACEBALL_BUTTON_D            0x0008
+#define  GLUT_SPACEBALL_BUTTON_E            0x0010
 
 /*
  * Initialization functions, see fglut_init.c