hook_menu_example

gistfile1.php

<?php
/**
 * Implements hook_menu().
 */
function mymodule_menu() {
  $items['user/%user/bb_licenses/%'] = array(
    'title' => 'Saludar',
    'page callback' => 'gestionar_licencia',
    'page arguments' => array(1,3),
    'type' => MENU_CALLBACK,
    'access callback' => user_access('my permission'),
  );

  return $items;
}

/** 
 * Do a thing.
 * 
 * @param object $user
 *   Fully loaded user object.
 * @param $argument
 *   Some argument.
 * 
 * @see mymodule_menu()
 * @see user_load()
 */
function gestionar_licensia($user, $argument) {
  return t('This is my argument: @argument', array('@argument' => $argument));
}