Fix Mutex problem

gtk/src/gtk_s9x.cpp

@@ -44,6 +44,7 @@ main (int argc, char *argv[])
 
     g_thread_init (NULL);
     gdk_threads_init ();
+    gdk_threads_enter ();
 
     gtk_init (&argc, &argv);
 
@@ -126,7 +127,7 @@ main (int argc, char *argv[])
     gtk_window_present (top_level->get_window ());
 
     gtk_main ();
-
+    gdk_threads_leave ();
     return 0;
 }