Change the number of results in search

By default in Drupal 5 is not possible to change the number of results per page in search.

I've search in module search and in line 871 we can see:

$result = pager_query("SELECT * FROM temp_search_results", 10, 0, $count_query);

so it's true the number of results can be changed, it's always 10.

Is it possible to make the followings changes in the search.module?

In line 871:

instead of:

$result = pager_query("SELECT * FROM temp_search_results", 10, 0, $count_query);

replaced by

$result = pager_query("SELECT * FROM temp_search_results", variable_get('search_num_results',10), 0, $count_query);

and in the function search_admin_settings insert:

  $form['num_results'] = array('#type' => 'fieldset',
                   '#title' => t('Number of results per page'));
  $form['num_results']['search_num_results'] = array('#type' => 'textfield',
                        '#title' => t('Results number'),
                        '#default_value' => variable_get('search_num_results', 10),
                        '#size' => 5,
                        '#maxlength' => 3,
                        '#description' => t('The number of results to show per page'));

I don't know if it can be changed in Drupal 5 (i think is not possible) but is it possible for 6?