Index: src/tetrinet.c
===================================================================
--- src/tetrinet.c
+++ src/tetrinet.c	2009-03-29 16:20:19.000000000 +0200
@@ -232,7 +232,7 @@
             dialog = gtk_message_dialog_new (NULL, GTK_DIALOG_MODAL,
                                              GTK_MESSAGE_ERROR,
                                              GTK_BUTTONS_OK,
-                                             buf);
+                                             "%s", buf);
             gtk_dialog_run (GTK_DIALOG(dialog));
             gtk_widget_destroy (dialog);
             g_free (data_utf8);