--- source/unix/gtkui/gtkui.cpp.old	2015-11-11 09:13:57.417684436 +0100
+++ source/unix/gtkui/gtkui.cpp	2015-11-11 09:14:12.176407155 +0100
@@ -317,7 +317,7 @@
 				GTK_DIALOG_DESTROY_WITH_PARENT,
 				GTK_MESSAGE_INFO,
 				GTK_BUTTONS_OK,
-				message);
+				"%s", message);
 	gtk_dialog_run(GTK_DIALOG(messagewindow));
 	gtk_widget_destroy(messagewindow);
 }