Another pair of eyes? It has to be something simple. Form not showing up at path.

Hi There -

Am having a heck of a time with this. This is the first time I've made a module with the menu system or a form. I'm able to get the title to show up on the page but nothing else. It's supposed to be a form with a single text field and a submit button. The reason it has to be something simple is that there just isn't that much here to mess up. The module is enabled.

I've searched for everything I can think of but there's nothing I can find that has helped. I'm hoping that it's something glaringly obvious to someone experienced with these things. Please have a look. I'm leaving some of the things I've tried in place, but commented out.

<?php

/**
 * Implementation of hook_menu
 */  

function example_menu($may_cache) {
  $items = array();

  if ($may_cache) {
     $items[] = array(
       'path' => 'admin/example',
       'title' => t('Example Form'),
       //'callback' => 'example_page',
       'callback' => 'drupal_get_form',
       'callback arguments' => array('example_form'),
       //'type' => MENU_CALLBACK,
       'access' => 'does stuff with one field',
       //'pid' => 390,
      ); 
  }
return $items;
}

/**
 * Implementation of hook_form()
 */ 

function example_form() {

  //$form['example']['add_nid'] = array(
  $form['add_nid'] = array(
  '#type' => 'textfield',
  '#title' => t('put nid here'),
  '#size' => 30,
  '#rows' => 1,
  '#description' => t('Enter nid.'),
  '#required' => TRUE,
  );

  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('submit'),
  );
}

function example_form_validate($form_id, $form_values) {
 // Do stuff with $form_values here and set errors if needed.
}

function example_form_submit($form_id, $form_values) {
  // has been tested on a php-page and works.

  return drupal_set_message('Thank you for submitting the form!');
}
/*
function example_page() {
  return drupal_get_form('example_form');
}
*/
?>