docs: protected Event handleException(final J2EContext webContext, final BaseClient<Credentials, CommonProfile> client, final Exception e) {
          if (e instanceof RequestSloException) {
              try {
                  webContext.getResponse().sendRedirect("logout");
              } catch (final IOException ioe) {
                  throw new IllegalArgumentException("Unable to call logout", ioe);
              }
              return stopWebflow();
          }
          val msg = String.format("Delegated authentication has failed with client %s", client.getName());
          LOGGER.error(msg, e);
          throw new IllegalArgumentException(msg);
      }