diff --git a/api/graphics_api.h b/api/graphics_api.h
index 1bcd307795..da5e06fe18 100755
--- a/api/graphics_api.h
+++ b/api/graphics_api.h
@@ -39,7 +39,7 @@ extern void app_graphics_reread_prefs(void);
     // called in the graphics thread
 extern void app_graphics_resize(int width, int height);
 extern void boinc_app_mouse_button(int x, int y, int which, int is_down);
-extern void boinc_app_mouse_move(int x, int y, bool left, int middle, int right);
+extern void boinc_app_mouse_move(int x, int y, int left, int middle, int right);
 extern void boinc_app_key_press(int, int);
 extern void boinc_app_key_release(int, int);