Access Denied error(403 Forbidden error)

Hi, I am new to drupal.. I have implemented an auto-fill search functionality in my project. I is working fine when am logged in as admin but when i logged out I does not work and gives error 403 forbidded error or access denied. Here is my coding..

<?php

/**

* Implementation of hook_perm().

*/

function search_tours_perm() {

return array('Allow user to search tours','Allow user to search tours');

}

/**

* Implementation of hook_menu().

*/

function search_tours_menu() {

$items['search_tours/tours'] = array(

'page callback' => 'search_tours',

'access callback' => 'user_access',

'access arguments' => array('Allow user to search tours;'),
'access'=> TRUE,

'type' => MENU_CALLBACK,

);
return $items;
}

/*

* Implementation of hook_block

*/

drupal_add_js(drupal_get_path('module', 'search_tours') .'/js/search_tours.js');
drupal_add_css(drupal_get_path('module', 'search_tours') .'/css/search_tours.css');

function search_tours_block($op = 'list', $delta = 0, $edit = array()) {

// The $op parameter determines what piece of information is being requested.

switch ($op) {

case 'list':

// If $op is "list", we just need to return a list of block descriptions.

// This is used to provide a list of possible blocks to the administrator,

// end users will not see these descriptions.

$blocks[0] = array(

'info' => t('Auto Complete search tour '),

);

// A block can provide default settings. In this case we'll enable the

// block and make it visible only on the 'node/*' pages.

$blocks[1] = array(

'info' => t('Example: empty block'),

'status' => TRUE,

'weight' => 0,

'visibility' => 1,

'pages' => 'node/*',

);

return $blocks;

case 'configure':

// If $op is "configure", we need to provide the administrator with a

// configuration form. The $delta parameter tells us which block is being

// configured. In this example, we'll allow the administrator to customize

// the text of the first block.

$form = array();

if ($delta == 0) {

// All we need to provide is a text field, Drupal will take care of

// the other block configuration options and the save button.

$form['block_example_string'] = array(

'#type' => 'textfield',

'#title' => t('Block contents'),

'#size' => 60,

'#description' => t('This string will appear in the example block.'),

'#default_value' => variable_get('block_example_string', t('Some example content.')),

);
}

return $form;

case 'save':

// If $op is "save", we need to save settings from the configuration form.

// Since the first block is the only one that allows configuration, we

// need to check $delta to make sure we only save it.

if ($delta == 0) {

// Have Drupal save the string to the database.

variable_set('block_example_string', $edit['block_example_string']);

}

return;

case 'view': default:

// If $op is "view", then we need to generate the block for display

// purposes. The $delta parameter tells us which block is being requested.

switch ($delta) {

case 0:

// The subject is displayed at the top of the block. Note that it

// should be passed through t() for translation.

$block['subject'] = t(' ');

// The content of the block is typically generated by calling a custom

// function.

$block['content'] = search_tours_block_contents(1);
}

return $block;

}

}

function search_tours_block_contents($which_block) {

global $base_url;

$search_tours = '

';
return variable_get('block_search_tours',t($search_tours));
}

function search_tours() {

$value = $_POST['searchkey'];
$count_answers = db_result(db_query("select count(*) from node where title like ('" .$value . "%') and type = 'tour' "));
if($count_answers == '0')
{
$html = '

• No Result for '. $value.'
';
}
else
{
$search_tours = "SELECT * FROM content_type_tour AS t1 INNER JOIN content_type_tourpricing AS t2 ON t1.nid = t2.field_tourname_nid inner join node as t3 on t1.nid = t3.nid where title like ('" .$value . "%')";
$result_search_tours = db_query($search_tours);
$html .= '

';
while ($row_search_tours = db_fetch_object( $result_search_tours)) {

$html .= '

• field_tourname_nid.'">'.$row_search_tours->title.'

  '.$row_search_tours->field_duration_value.' Days

';

}
$html .= '

';
}
return drupal_json(array('request' => 'valid', 'result'=>'false' , "html"=>$html ));

}