Autocomplete path problem - error 403 received.

Hi everybody,

long waiting for final CCK & Views modules forced me to create my own one. I would like to use the autocomplete feature in one of the form's fields, however, when I start typing in it I am getting js alert window with 403 error (access denied, or sth similar).
I've been googlin' a bit but I wasn't able to find appropriate answer. One reason for this might be clean URLs, but I don't use them. If you have any idea what might be wrong I would appreciate your help. This is my kalendar.module code:

<?php
function kalendar_autocomplete($string) {
  $matches = array();
  $result = db_query_range("SELECT nid, title FROM {node}");
  while ($node = db_fetch_object($result)) {
    $matches[$node->name] = check_plain($node->name);
  }
  print drupal_to_js($matches);
  exit();
}

//
// and this is what I have in kalendar_menu:
//
   $items['kalendar/autocomplete'] = array(
     'path' => 'kalendar/autocomplete',
     'title' => t('kalendar autocomplete'),
     'callback' => 'kalendar_autocomplete',
     'access arguments' => array('create kalendar'),
     'type' => MENU_CALLBACK
   );

?>

Thanks,
Petiar