--- srcORIG/gnubiff.cc	
+++ srcORIG/gnubiff.cc	
@@ -43,6 +43,7 @@ 
 #include "ui-preferences.h"
 #include "ui-applet.h"
 #include "ui-applet-gtk.h"
+#include <stdlib.h>
 
 int main (int argc, char **argv);
 int mainGNOME (int argc, char **argv);
--- srcORIG/gui.cc	
+++ srcORIG/gui.cc	
@@ -33,6 +33,7 @@ 
 #include <gmodule.h>
 #include "gtk_image_animation.h"
 #include "gui.h"
+#include <stdlib.h>
 
 
 /**
--- srcORIG/signals.cc	
+++ srcORIG/signals.cc	
@@ -32,6 +32,7 @@ 
 #include "signals.h"
 #include "ui-applet.h"
 #include "ui-applet-gui.h"
+#include <stdlib.h>
 
 /// Pointer to biff
 class Biff *Signals::biff_ = NULL;