--- xfce4-mount-plugin-0.5.5/panel-plugin/mount-plugin.c
+++ xfce4-mount-plugin-0.5.5/panel-plugin/mount-plugin.c
@@ -20,6 +20,7 @@ along with this program; if not, write t
 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
 #include "mount-plugin.h"
+#include <stdlib.h>
 
 static void
 on_message_dialog_response (GtkWidget *widget, gpointer *data)