diff --git a/includes/geo/sceneindex.php b/includes/geo/sceneindex.php
index e7ac4a1..557db30 100755
--- a/includes/geo/sceneindex.php
+++ b/includes/geo/sceneindex.php
@@ -1,218 +1,218 @@
 <?php
 
 /**
  * Geo scene index class.
  *
  * Zed. The immensity of stars. The HyperShip. The people.
  *
  * (c) 2010, Dereckson, some rights reserved.
  * Released under BSD license.
  *
  * @package     Zed
  * @subpackage  Geo
  * @author      Sébastien Santoro aka Dereckson <dereckson@espace-win.org>
  * @copyright   2010 Sébastien Santoro aka Dereckson
  * @license     http://www.opensource.org/licenses/bsd-license.php BSD
  * @version     0.1
  * @link        http://scherzo.dereckson.be/doc/zed
  * @link        http://zed.dereckson.be/
  * @filesource
  *
  * This class implements a singleton pattern.
  */
 
 require_once('includes/cache/cache.php');
 
 /**
  * Geo scene class
  *
  * This class provides an index of available scene template files.
  */
 class GeoSceneIndex {
     /**
      * Global location templates array
      *
      * Keys are global location codes.
      * Values the relevant template file.
      *
      * @var Array
      */
     public $global_templates;
 
     /**
      * Local location templates 2D array
      *
      * Keys are global and local location codes.
      * Values the relevant template file.
      *
      * e.g. $local_templates['B00017001']['(10, 50, 8)'] => 'B00017_port.tpl'
      *
      * @var Array
      */
     public $local_templates;
 
     /**
      * Time of the last updated file in the scenes directory
      *
      * @var int
      */
     public $updated;
 
     /**
      * The directory where templates are stored
      *
      * @var string
      */
     public $directory;
 
     /**
      * The current index instance array
      *
      * Keys are scene directories (string)
      * Items are GeoSceneIndex instances
      *
      * @var Array
      */
     static $instance = [];
 
     /**
      * Gets the index instance, initializing it if needed
      *
      * @return index the index instance
      */
     static function load ($directory) {
         //Creates the index object if needed
         if (!array_key_exists($directory, self::$instance)) {
             self::$instance[$directory] = new GeoSceneIndex($directory);
         }
 
         return self::$instance[$directory];
     }
 
     /**
      * Initializes a new GeoSceneIndex instance
      *
      * @param string $directory the scene templates directory
      */
     public function __construct ($directory) {
         $this->directory = $directory;
         if (!$this->get_cached_information() || !$this->is_up_to_date()) {
                 $this->refresh_information();
                 $this->set_cached_information();
         }
     }
 
     /**
      * Caches index data
      */
     public function set_cached_information () {
         $cache = Cache::load();
         $cache->set('zed_sceneindex', serialize($this));
     }
 
     /**
      * Gets index from cache
      */
     public function get_cached_information () {
         $cache = Cache::load();
         $cached_index =$cache->get('zed_sceneindex');
         if ($index = unserialize($cache->get('zed_sceneindex'))) {
             $index = unserialize($cache->get('zed_sceneindex'));
             $this->global_templates = $index->global_templates;
             $this->local_templates = $index->local_templates;
             $this->updated = $index->updated;
             $this->directory = $index->directory;
             return true;
         }
         return false;
     }
 
     /**
      * Reads scene templates and indexes information
      */
     public function refresh_information () {
         $this->global_templates = [];
         $this->local_templates = [];
         $this->updated = filemtime($this->directory);
         if ($handle = opendir($this->directory)) {
             while (false !== ($file = readdir($handle))) {
                  if (GeoScene::get_file_extension($file) == 'tpl') {
-                    $template = file_get_contents($this->directory . '/' . $file, false, NULL, 0, 1024);
+                    $template = file_get_contents($this->directory . '/' . $file, false, null, 0, 1024);
                     $location = self::get_template_location($template);
-                    if ($location[1] !== NULL) {
+                    if ($location[1] !== null) {
                         $this->local_templates[$location[0]][$location[1]] = $file;
-                    } elseif ($location[0] != NULL) {
+                    } elseif ($location[0] != null) {
                         $this->global_templates[$location[0]] = $file;
                     }
                  }
             }
             closedir($handle);
         }
     }
 
     /**
      * Determines if the information is still up to date
      *
      * @return bool true if the information is up to date ; otherwise, false.
      */
     public function is_up_to_date () {
         return ($this->updated == filemtime($this->directory));
     }
 
     /**
      * Gets template location
      *
      * @return Array an string array of the location (two items; global, local)
      *  At key 0, a string with global location, or NULL if not specified
      *  At key 1, a string with local location, or NULL if not specified
      */
     private static function get_template_location ($template) {
-        $location = [NULL, NULL];
+        $location = [null, null];
 
         //Gets global location
         $pos1 = strpos($template, "Global location: ");
         if ($pos1 === false) {
             throw new Exception("No location in template. Any template file must contain a comment line with the string 'Global location: ' followed by the global location matching the template. It should also contains a line 'Local location: ' when applicable.");
         }
         $pos1 += 17;
         $pos2 = strpos($template, "\n", $pos1);
         $location[0] = trim(substr($template, $pos1, $pos2 - $pos1));
 
         //Gets local location
         $pos1 = strpos($template, "Local location: ");
         if ($pos1 !== false) {
             $pos1 += 16;
             $pos2 = strpos($template, "\n", $pos1);
             $location[1] = trim(substr($template, $pos1, $pos2 - $pos1));
         }
 
         return $location;
     }
 
     /**
      * Gets local template file from index
      *
      * @param string $location_global the global location
      * @param string $location_global the local location
      * @return string the relevant template scene file, or NULL if not existing
      */
     public function get_local_template ($location_global, $location_local) {
         if (isset($this->local_templates[$location_global][$location_local])) {
             return $this->local_templates[$location_global][$location_local];
         }
-        return NULL;
+        return null;
     }
 
     /**
      * Gets global template file from index
      *
      * @param string $location_global the global location
      * @return string the relevant template scene file, or NULL if not existing
      */
     public function get_global_template ($location_global) {
         if (isset($this->global_templates[$location_global])) {
             return $this->global_templates[$location_global];
         }
-        return NULL;
+        return null;
     }
 }
diff --git a/includes/objects/invite.php b/includes/objects/invite.php
index 784e2d8..b3c8dc9 100755
--- a/includes/objects/invite.php
+++ b/includes/objects/invite.php
@@ -1,197 +1,197 @@
 <?php
 
 /**
  * User invite class
  *
  * Zed. The immensity of stars. The HyperShip. The people.
  *
  * (c) 2010, Dereckson, some rights reserved.
  * Released under BSD license.
  *
  * 0.1    2010-06-29 02:13    Initial version [DcK]
  *
  * @package     Zed
  * @subpackage  Model
  * @author      Sébastien Santoro aka Dereckson <dereckson@espace-win.org>
  * @copyright   2010 Sébastien Santoro aka Dereckson
  * @license     http://www.opensource.org/licenses/bsd-license.php BSD
  * @version     0.1
  * @link        http://scherzo.dereckson.be/doc/zed
  * @link        http://zed.dereckson.be/
  * @filesource
  */
 
 /**
  * User invite class
  *
  * This class maps the users_invites table.
  */
 class Invite {
 
     public $code;
     public $date;
     public $from_user_id;
     public $from_perso_id;
 
     /**
      * The user_id who have been claimed the invite
      * Will be NULL as long as the invite haven't been claimed
      *
      * @var int
      */
-    public $to_user_id = NULL;
+    public $to_user_id = null;
 
     /**
      * Initializes a new instance
      *
      * @param int $code the primary key
      */
-    function __construct ($code = NULL) {
+    function __construct ($code = null) {
         if ($code) {
             $this->code = $code;
             $this->load_from_database();
         } else {
             //New invite code
             $this->generate_code();
             $this->date = time();
         }
     }
 
     /**
      * Generates a unique invite code and sets it in the code property.
      */
     function generate_code () {
         global $db;
 
         do {
             $this->code = generate_random_string("AAA111");
             $sql = "SELECT COUNT(*) FROM " . TABLE_USERS_INVITES . " WHERE invite_code = '$this->code' LOCK IN SHARE MODE;";
             if (!$result = $db->sql_query($sql)) {
                 message_die(SQL_ERROR, "Can't access invite users table", '', __LINE__, __FILE__, $sql);
             }
             $row = $db->sql_fetchrow($result);
         } while ($row[0]);
     }
 
     /**
      * Loads the object Invite (ie fill the properties) from the database
      */
     function load_from_database () {
         global $db;
         $code = $db->sql_escape($this->code);
         $sql = "SELECT * FROM " . TABLE_USERS_INVITES . " WHERE invite_code = '" . $code . "'";
         if ( !($result = $db->sql_query($sql)) ) {
             message_die(SQL_ERROR, "Unable to query invite codes", '', __LINE__, __FILE__, $sql);
         }
         if (!$row = $db->sql_fetchrow($result)) {
             $this->lastError = "Invite code unknown: " . $this->code;
             return false;
         }
         $this->code = $row['invite_code'];
         $this->date = $row['invite_date'];
         $this->from_user_id = $row['invite_from_user_id'];
         $this->from_perso_id = $row['invite_from_perso_id'];
         $this->to_user_id = $row['invite_to_user_id'];
 
         return true;
     }
 
     /**
      * Determines whether the current invite code have been claimed by an user.
      *
      * @return true if the code have been claimed ; otherwise, false.
      */
     function is_claimed () {
         return (bool)$this->to_user_id;
     }
 
     /**
      * Saves to database
      */
     function save_to_database () {
         global $db;
 
         $code = $db->sql_escape($this->code);
         $date = $db->sql_escape($this->date);
         $from_user_id = $db->sql_escape($this->from_user_id);
         $from_perso_id = $db->sql_escape($this->from_perso_id);
         $to_user_id = $this->to_user_id ? "'" . $db->sql_escape($this->to_user_id) . "'" : 'NULL';
 
         //Updates or inserts
         $sql = "REPLACE INTO " . TABLE_USERS_INVITES . " (`invite_code`, `invite_date`, `invite_from_user_id`, `invite_from_perso_id`, `invite_to_user_id`) VALUES ('$code', '$date', '$from_user_id', '$from_perso_id', $to_user_id)";
         if (!$db->sql_query($sql)) {
             message_die(SQL_ERROR, "Unable to save invite code", '', __LINE__, __FILE__, $sql);
         }
     }
 
     /**
      * Deletes the invite
      */
     function delete () {
         global $db;
         $code = $db->sql_escape($this->code);
         $sql = "DELETE FROM " . TABLE_USERS_INVITES . " WHERE invite_code = '$code'";
         if (!$db->sql_query($sql)) {
             message_die(SQL_ERROR, "Unable to save delete code", '', __LINE__, __FILE__, $sql);
         }
     }
 
     /**
      * Creates an invite code
      *
      * @param int $user_id user id
      * @param int $perso_id perso id
      * @return string the invite code
      */
     static function create ($user_id, $perso_id) {
         $invite = new Invite();
         $invite->from_perso_id = $perso_id;
         $invite->from_user_id = $user_id;
         $invite->save_to_database();
         return $invite->code;
     }
 
     /**
      * Gets invites generated by the specified perso ID
      *
      * @param int $perso_id the perso whom to get the invites
      * @return Array an array of string, each line being an invite code
      */
     static function get_invites_from ($perso_id) {
         global $db;
         $sql = "SELECT invite_code FROM " . TABLE_USERS_INVITES
              . " WHERE invite_from_perso_id = $perso_id AND invite_to_user_id IS NULL ORDER BY invite_date ASC";
         if (!$result = $db->sql_query($sql)) {
             message_die(SQL_ERROR, "Can't access invite users table", '', __LINE__, __FILE__, $sql);
         }
         $codes = [];
         while ($row = $db->sql_fetchrow($result)) {
             $codes[] = $row['invite_code'];
         }
         return $codes;
     }
 
     /**
      * Gets the perso ID who invited the specified perso
      *
      * @param int $perso_id the perso whom to get the invites
      * @return int|null the perso whom to get the invites ; or null, if nobody have invited him
      */
     static function who_invited ($perso_id) {
         global $db;
         $perso = Perso::get($perso_id);
 
         if ($user_id = $perso->user_id) {
             $sql = "SELECT invite_from_perso_id FROM " . TABLE_USERS_INVITES . " WHERE invite_to_user_id = '$user_id'";
             if (!$result = $db->sql_query($sql)) {
                 message_die(SQL_ERROR, "Can't access invite users table", '', __LINE__, __FILE__, $sql);
             }
             if ($row = $db->sql_fetchrow($result)) {
                 return $row[0];
             }
         }
 
         return null;
     }
 
 }
diff --git a/includes/objects/port.php b/includes/objects/port.php
index 23185a6..750276a 100755
--- a/includes/objects/port.php
+++ b/includes/objects/port.php
@@ -1,211 +1,211 @@
 <?php
 
 /**
  * Port class
  *
  * Zed. The immensity of stars. The HyperShip. The people.
  *
  * (c) 2010, Dereckson, some rights reserved.
  * Released under BSD license.
  *
  * 0.1    2010-02-09 19:17    Autogenerated by Pluton Scaffolding
  *
  * @package     Zed
  * @subpackage  Model
  * @author      Sébastien Santoro aka Dereckson <dereckson@espace-win.org>
  * @copyright   2010 Sébastien Santoro aka Dereckson
  * @license     http://www.opensource.org/licenses/bsd-license.php BSD
  * @version     0.1
  * @link        http://scherzo.dereckson.be/doc/zed
  * @link        http://zed.dereckson.be/
  * @filesource
  */
 
 require_once("includes/geo/location.php");
 
 /**
  * Port class
  *
  * This class maps the ports table.
  *
  * The class also provides helper methods to handle ports at specified location.
  */
 class Port {
 
     public $id;
     public $location_global;
     public $location_local;
     public $name;
 
     public $hidden;
     public $requiresPTA;
     public $default;
 
     /**
      * Initializes a new instance
      * @param int $id the primary key
      */
-    function __construct ($id = NULL) {
+    function __construct ($id = null) {
         if ($id) {
             $this->id = $id;
             $this->load_from_database();
         }
     }
 
     /**
      * Loads the object Port (ie fill the properties) from the $_POST array
      */
     function load_from_form () {
         if (array_key_exists('location_global', $_POST)) {
             $this->location_global = $_POST['location_global'];
         }
         if (array_key_exists('location_local', $_POST)) {
             $this->location_local = $_POST['location_local'];
         }
         if (array_key_exists('name', $_POST)) {
             $this->name = $_POST['name'];
         }
 
         if (array_key_exists('hidden', $_POST)) {
             $this->hidden = $_POST['hidden'] ? true : false;
         }
         if (array_key_exists('requiresPTA', $_POST)) {
             $this->requiresPTA = $_POST['requiresPTA'] ? true : false;
         }
         if (array_key_exists('default', $_POST)) {
             $this->hidden = $_POST['default'] ? true : false;
         }
     }
 
     /**
      * Loads the object Port (ie fill the properties) from the database
      */
     function load_from_database () {
         global $db;
         $id = $db->sql_escape($this->id);
         $sql = "SELECT * FROM " . TABLE_PORTS . " WHERE port_id = '" . $id . "'";
         if ( !($result = $db->sql_query($sql)) ) {
             message_die(SQL_ERROR, "Unable to query ports", '', __LINE__, __FILE__, $sql);
         }
         if (!$row = $db->sql_fetchrow($result)) {
             $this->lastError = "Port unknown: " . $this->id;
             return false;
         }
         $this->location_global = $row['location_global'];
         $this->location_local = $row['location_local'];
         $this->name = $row['port_name'];
 
         //Explodes place_status SET field in boolean variables
         if ($row['place_status']) {
             $flags = explode(',', $row['port_status']);
             foreach ($flags as $flag) {
                 $this->$flag = true;
             }
         }
 
         return true;
     }
 
     /**
      * Gets status field value
      *
      * @return string the status field value (e.g. "requiresPTA,default")
      */
     function getStatus () {
         $flags = ['hidden', 'requiresPTA', 'default'];
         foreach ($flags as $flag) {
             if ($this->$flag) {
                 $status[] = $flag;
             }
         }
         return implode(',', $status);
     }
 
     /**
      * Saves to database
      */
     function save_to_database () {
         global $db;
 
         $id = $this->id ? "'" . $db->sql_escape($this->id) . "'" : 'NULL';
         $location_global = $db->sql_escape($this->location_global);
         $location_local = $db->sql_escape($this->location_local);
         $name = $db->sql_escape($this->name);
         $status = $this->getStatus();
 
         //Updates or inserts
         $sql = "REPLACE INTO " . TABLE_PORTS . " (`port_id`, `location_global`, `location_local`, `port_name`, `port_status`) VALUES ($id, '$location_global', '$location_local', '$name', '$status')";
         if (!$db->sql_query($sql)) {
             message_die(SQL_ERROR, "Unable to save", '', __LINE__, __FILE__, $sql);
         }
 
         if (!$id) {
             //Gets new record id value
             $this->id = $db->sql_nextid();
         }
     }
 
     /**
      * Determines if the specified location have a port
      *
      * @param string $location_global the global location
      * @return boolean true if there is a spatioport exactly at the specified location ; otherwise, false.
      */
     static function have_port ($location_global) {
-        return (get_port_id($location_global) !== NULL);
+        return (get_port_id($location_global) !== null);
     }
 
     /**
      * Gets the port situated exactly at the specified global location
      *
      * @param string $location_global the global location
      * @return int the port ID
      */
     static function get_port_id ($location_global) {
         global $db;
         $location_global = $db->sql_escape($location_global);
         $sql = "SELECT port_id FROM " . TABLE_PORTS . " WHERE location_global = '$location_global'";
         if (!$result = $db->sql_query($sql)) {
             message_die(SQL_ERROR, "Unable to get ports", '', __LINE__, __FILE__, $sql);
         }
         if ($row = $db->sql_fetchrow($result)) {
            return $row['port_id'];
         }
         return null;
     }
 
     /**
      * Gets default port, from specified global location
      *
      * @param string $location_global the global location
      * @return Port the port near this location ; null if there isn't port there.
      */
     static function from_location ($location_global) {
         $havePlace = strlen($location_global) == 9;
         $port_id = null;
 
         if ($havePlace) {
             //Checks if there's a port at specified location
             $port_id = self::get_port_id($location_global);
         }
 
         if ($port_id == null) {
             //Nearest default port.
             //If place have been specified (B0001001), we've to found elsewhere
             //==> B00001%
             global $db;
             $loc = $db->sql_escape(substr($location_global, 0, 6));
             $sql = "SELECT port_id FROM " . TABLE_PORTS . " WHERE location_global LIKE '$loc%'";
             if (!$result = $db->sql_query($sql)) {
                 message_die(SQL_ERROR, "Can't get port", '', __LINE__, __FILE__, $sql);
             }
             if ($row = $db->sql_fetchrow($result)) {
                 $port_id = $row['port_id'];
             } else {
                 return null;
             }
         }
 
         return new Port($port_id);
      }
 }
diff --git a/includes/objects/request.php b/includes/objects/request.php
index a603c05..3ff377a 100755
--- a/includes/objects/request.php
+++ b/includes/objects/request.php
@@ -1,143 +1,143 @@
 <?php
 
 /**
  * Request class
  *
  * Zed. The immensity of stars. The HyperShip. The people.
  *
  * (c) 2011, Dereckson, some rights reserved.
  * Released under BSD license.
  *
  * 0.1    2011-06-13 21:16    Autogenerated by Pluton Scaffolding
  *
  * @package     Zed
  * @subpackage  Model
  * @author      Sébastien Santoro aka Dereckson <dereckson@espace-win.org>
  * @copyright   2011 Sébastien Santoro aka Dereckson
  * @license     http://www.opensource.org/licenses/bsd-license.php BSD
  * @version     0.1
  * @link        http://scherzo.dereckson.be/doc/zed
  * @link        http://zed.dereckson.be/
  * @filesource
  */
 
 /**
  * Request class
  *
  * This class maps the requests table.
  */
 class Request {
 
     public $id;
     public $code;
     public $title;
     public $date;
     public $author;
     public $to;
     public $message;
     public $location_global;
     public $location_local;
     public $status;
 
     /**
      * Initializes a new instance
      * @param int $id the primary key
      */
-    function __construct ($id = NULL) {
+    function __construct ($id = null) {
         if ($id) {
             $this->id = $id;
             $this->load_from_database();
         } else {
            $this->date = time();
            $this->status = 'NEW';
         }
     }
 
     /**
      * Loads the object Request (ie fill the properties) from the $_POST array
      */
     function load_from_form () {
         if (array_key_exists('code', $_POST)) {
             $this->code = $_POST['code'];
         }
         if (array_key_exists('title', $_POST)) {
             $this->title = $_POST['title'];
         }
         if (array_key_exists('date', $_POST)) {
             $this->date = $_POST['date'];
         }
         if (array_key_exists('author', $_POST)) {
             $this->author = $_POST['author'];
         }
         if (array_key_exists('to', $_POST)) {
             $this->to = $_POST['to'];
         }
         if (array_key_exists('message', $_POST)) {
             $this->message = $_POST['message'];
         }
         if (array_key_exists('location_global', $_POST)) {
             $this->location_global = $_POST['location_global'];
         }
         if (array_key_exists('location_local', $_POST)) {
             $this->location_local = $_POST['location_local'];
         }
         if (array_key_exists('status', $_POST)) {
             $this->status = $_POST['status'];
         }
     }
 
     /**
      * Loads the object Request (ie fill the properties) from the database
      */
     function load_from_database () {
         global $db;
         $id = $db->sql_escape($this->id);
         $sql = "SELECT * FROM " . TABLE_REQUESTS . " WHERE request_id = '" . $id . "'";
         if (!$result = $db->sql_query($sql)) {
             message_die(SQL_ERROR, "Unable to query requests", '', __LINE__, __FILE__, $sql);
         }
         if (!$row = $db->sql_fetchrow($result)) {
             $this->lastError = "Request unknown: " . $this->id;
             return false;
         }
         $this->code = $row['request_code'];
         $this->title = $row['request_title'];
         $this->date = $row['request_date'];
         $this->author = $row['request_author'];
         $this->message = $row['request_message'];
         $this->to = $row['request_to'];
         $this->location_global = $row['location_global'];
         $this->location_local = $row['location_local'];
         $this->status = $row['request_status'];
         return true;
     }
 
     /**
      * Saves to database
      */
     function save_to_database () {
         global $db;
 
         $id = $this->id ? "'" . $db->sql_escape($this->id) . "'" : 'NULL';
         $code = $db->sql_escape($this->code);
         $title = $db->sql_escape($this->title);
         $date = $db->sql_escape($this->date);
         $author = $db->sql_escape($this->author);
         $message = $db->sql_escape($this->message);
         $to = $db->sql_escape($this->to);
         $location_global = $db->sql_escape($this->location_global);
         $location_local = $db->sql_escape($this->location_local);
         $status = $db->sql_escape($this->status);
 
         //Updates or inserts
         $sql = "REPLACE INTO " . TABLE_REQUESTS . " (`request_id`, `request_code`, `request_title`, `request_date`, `request_author`, `request_message`, `request_to`, `location_global`, `location_local`, `request_status`) VALUES ('$id', '$code', '$title', '$date', '$author', '$message', '$to', '$location_global', '$location_local', '$status')";
         if (!$db->sql_query($sql)) {
             message_die(SQL_ERROR, "Unable to save", '', __LINE__, __FILE__, $sql);
         }
 
         if (!$this->id) {
             //Gets new record id value
             $this->id = $db->sql_nextid();
         }
     }
 }
diff --git a/includes/objects/requestreply.php b/includes/objects/requestreply.php
index b79fb9f..2d5c35c 100755
--- a/includes/objects/requestreply.php
+++ b/includes/objects/requestreply.php
@@ -1,110 +1,110 @@
 <?php
 
 /**
  * RequestReply class
  *
  * Zed. The immensity of stars. The HyperShip. The people.
  *
  * (c) 2011, Dereckson, some rights reserved.
  * Released under BSD license.
  *
  * 0.1    2011-06-13 21:20    Autogenerated by Pluton Scaffolding
  *
  * @package     Zed
  * @subpackage  Model
  * @author      Sébastien Santoro aka Dereckson <dereckson@espace-win.org>
  * @copyright   2011 Sébastien Santoro aka Dereckson
  * @license     http://www.opensource.org/licenses/bsd-license.php BSD
  * @version     0.1
  * @link        http://scherzo.dereckson.be/doc/zed
  * @link        http://zed.dereckson.be/
  * @filesource
  */
 
 /**
  * RequestReply class
  *
  * This class maps the requests_replies table.
  */
 class RequestReply {
 
     public $id;
     public $request_id;
     public $author;
     public $date;
     public $text;
 
     /**
      * Initializes a new instance
      * @param int $id the primary key
      */
-    function __construct ($id = NULL) {
+    function __construct ($id = null) {
         if ($id) {
             $this->id = $id;
             $this->load_from_database();
         }
     }
 
     /**
      * Loads the object RequestReply (ie fill the properties) from the $_POST array
      */
     function load_from_form () {
         if (array_key_exists('request_id', $_POST)) {
             $this->request_id = $_POST['request_id'];
         }
         if (array_key_exists('author', $_POST)) {
             $this->author = $_POST['author'];
         }
         if (array_key_exists('date', $_POST)) {
             $this->date = $_POST['date'];
         }
         if (array_key_exists('text', $_POST)) {
             $this->text = $_POST['text'];
         }
     }
 
     /**
      * Loads the object RequestReply (ie fill the properties) from the database
      */
     function load_from_database () {
         global $db;
         $id = $db->sql_escape($this->id);
         $sql = "SELECT * FROM " . TABLE_REQUESTS_REPLIES . " WHERE request_reply_id = '" . $id . "'";
         if (!$result = $db->sql_query($sql)) {
             message_die(SQL_ERROR, "Unable to query requests_replies", '', __LINE__, __FILE__, $sql);
         }
         if (!$row = $db->sql_fetchrow($result)) {
             $this->lastError = "RequestReply unknown: " . $this->id;
             return false;
         }
         $this->request_id = $row['request_id'];
         $this->author = $row['request_reply_author'];
         $this->date = $row['request_reply_date'];
         $this->text = $row['request_reply_text'];
         return true;
     }
 
     /**
      * Saves to database
      */
     function save_to_database () {
         global $db;
 
         $id = $this->id ? "'" . $db->sql_escape($this->id) . "'" : 'NULL';
         $request_id = $db->sql_escape($this->request_id);
         $author = $db->sql_escape($this->author);
         $date = $db->sql_escape($this->date);
         $text = $db->sql_escape($this->text);
 
         //Updates or inserts
         $sql = "REPLACE INTO " . TABLE_REQUESTS_REPLIES . "(`request_reply_id`, `request_id`, `request_reply_author`, `request_reply_date`, `request_reply_text`) VALUES ('$id', '$request_id', '$author', '$date', '$text')";
         if (!$db->sql_query($sql)) {
             message_die(SQL_ERROR, "Unable to save", '', __LINE__, __FILE__, $sql);
         }
 
         if (!$this->id) {
             //Gets new record id value
             $this->id = $db->sql_nextid();
         }
     }
 }