add (new BookmarkablePageLink<Void>("register", ISIApplication.get().getRegisterPageClass()).setVisible(ISIApplication.get().isSelfRegisterOn()));
AuthApplication<User> app = null;
try { app = ((AuthApplication<User>)Application.get()); } catch (ClassCastException e) { }
if (app == null || !app.getSignInPageClass().isInstance(this))
throw new UnauthorizedInstantiationException(Login.class);
if (params != null) {
String username = params.getString("username");
String token = params.getString("token");
if (username != null && token != null) {