diff --git a/celestia/src/celengine/frametree.h b/celestia/src/celengine/frametree.h

index 2e1efa2..8ffff45 100644

--- a/celestia/src/celengine/frametree.h

+++ b/celestia/src/celengine/frametree.h

@@ -1,5 +1,4 @@

-// frametree.h

-//

+// frametree.h //

 // Reference frame tree.

 //

 // Copyright (C) 2008, the Celestia Development Team

@@ -14,6 +13,7 @@

 #define _CELENGINE_FRAMETREE_H_

 #include <vector>

+#include <libio.h>

 class Star;

 class Body;