diff --git a/main/admin/configure_inscription.php b/main/admin/configure_inscription.php
index e09c0fdc4f..8bac4e087e 100755
--- a/main/admin/configure_inscription.php
+++ b/main/admin/configure_inscription.php
@@ -109,7 +109,7 @@ if (!empty($homep_new)) {
 }
 
 if (!empty($action)) {
-    if ($_POST['formSent']) {
+    if (isset($_POST['formSent'])) {
         switch ($action) {
             case 'edit_top':
                 // Filter
diff --git a/main/inc/lib/statistics.lib.php b/main/inc/lib/statistics.lib.php
index 0532c42c5e..6e6b356874 100644
--- a/main/inc/lib/statistics.lib.php
+++ b/main/inc/lib/statistics.lib.php
@@ -96,9 +96,9 @@ class Statistics
     public static function countUsers($status = null, $categoryCode = null, $countInvisibleCourses = true, $onlyActive = false)
     {
         // Database table definitions
-        $course_user_table     = Database :: get_main_table(TABLE_MAIN_COURSE_USER);
-        $course_table         = Database :: get_main_table(TABLE_MAIN_COURSE);
-        $user_table         = Database :: get_main_table(TABLE_MAIN_USER);
+        $course_user_table = Database:: get_main_table(TABLE_MAIN_COURSE_USER);
+        $course_table = Database:: get_main_table(TABLE_MAIN_COURSE);
+        $user_table = Database:: get_main_table(TABLE_MAIN_USER);
         $access_url_rel_user_table= Database :: get_main_table(TABLE_MAIN_ACCESS_URL_REL_USER);
         $current_url_id = api_get_current_access_url_id();
         $active_filter = $onlyActive?' AND active=1':'';
@@ -107,22 +107,33 @@ class Statistics
         if (api_is_multiple_url_enabled()) {
             $sql = "SELECT COUNT(DISTINCT(u.user_id)) AS number
                 FROM $user_table as u, $access_url_rel_user_table as url
-                WHERE u.user_id=url.user_id
-                AND access_url_id='".$current_url_id."'
+                WHERE
+                    u.user_id = url.user_id AND
+                    access_url_id = '".$current_url_id."'
                 $status_filter $active_filter";
             if (isset ($categoryCode)) {
                 $sql = "SELECT COUNT(DISTINCT(cu.user_id)) AS number
                 FROM $course_user_table cu, $course_table c, $access_url_rel_user_table as url
-                WHERE c.id = cu.c_id
-                AND c.category_code = '".Database::escape_string($categoryCode)."'
-                AND cu.user_id=url.user_id AND access_url_id='".$current_url_id."'
-                $status_filter $active_filter";
+                WHERE
+                    c.id = cu.c_id AND
+                    c.category_code = '".Database::escape_string($categoryCode)."' AND
+                    cu.user_id = url.user_id AND
+                    access_url_id='".$current_url_id."'
+                    $status_filter $active_filter";
             }
         } else {
-            $sql = "SELECT COUNT(DISTINCT(user_id)) AS number FROM $user_table WHERE 1=1 $status_filter $active_filter";
+            $sql = "SELECT COUNT(DISTINCT(user_id)) AS number
+                    FROM $user_table WHERE 1=1 $status_filter $active_filter";
             if (isset ($categoryCode)) {
                 $status_filter = isset($status)?' AND status = '.intval($status):'';
-                $sql = "SELECT COUNT(DISTINCT(cu.user_id)) AS number FROM $course_user_table cu, $course_table c WHERE c.code = cu.course_code AND c.category_code = '".Database::escape_string($categoryCode)."' $status_filter $active_filter";
+                $sql = "SELECT COUNT(DISTINCT(cu.user_id)) AS number
+                    FROM $course_user_table cu, $course_table c
+                    WHERE
+                        c.id = cu.c_id AND
+                        c.category_code = '".Database::escape_string($categoryCode)."'
+                        $status_filter
+                        $active_filter
+                    ";
             }
         }
 
diff --git a/main/inc/lib/zombie/zombie_manager.class.php b/main/inc/lib/zombie/zombie_manager.class.php
index 0f57e6d094..68a4029abb 100755
--- a/main/inc/lib/zombie/zombie_manager.class.php
+++ b/main/inc/lib/zombie/zombie_manager.class.php
@@ -26,7 +26,7 @@ class ZombieManager
      * @param bool $active_only if true returns only active users. Otherwise returns all users.
      * @return ResultSet
      */
-    static function list_zombies($ceiling, $active_only = true)
+    static function listZombies($ceiling, $active_only = true, $count = 0, $from = 10, $column = 'user.firstname', $direction = 'desc')
     {
         $ceiling = is_numeric($ceiling) ? (int) $ceiling : strtotime($ceiling);
         $ceiling = date('Y-m-d H:i:s', $ceiling);
@@ -46,7 +46,6 @@ class ZombieManager
                     user.active,
                     access.login_date';
 
-        global $_configuration;
         if (api_is_multiple_url_enabled()) {
             $access_url_rel_user_table = Database :: get_main_table(TABLE_MAIN_ACCESS_URL_REL_USER);
             $current_url_id = api_get_current_access_url_id();
@@ -70,24 +69,31 @@ class ZombieManager
                         access.login_date <= '$ceiling' AND
                         user.user_id = access.login_user_id";
         }
-        if($active_only)
-        {
+        if ($active_only) {
             $sql .= ' AND user.active = 1';
         }
 
-        return ResultSet::create($sql);
+        $count = intval($count);
+        $from = intval($from);
+
+        $sql .=  " ORDER BY $column $direction";
+        $sql .= " LIMIT $count, $from ";
+
+        $result = Database::query($sql);
+
+        return Database::store_result($result, 'ASSOC');
     }
 
+    /**
+     * @param $ceiling
+     */
     static function deactivate_zombies($ceiling)
     {
         $zombies = self::list_zombies($ceiling);
         $ids  = array();
-        foreach($zombies as $zombie)
-        {
+        foreach($zombies as $zombie) {
             $ids[] = $zombie['user_id'];
         }
         UserManager::deactivate_users($ids);
     }
-
-
 }
diff --git a/main/inc/lib/zombie/zombie_report.class.php b/main/inc/lib/zombie/zombie_report.class.php
index 24510ceca8..cc73b7d47c 100755
--- a/main/inc/lib/zombie/zombie_report.class.php
+++ b/main/inc/lib/zombie/zombie_report.class.php
@@ -31,7 +31,7 @@ class ZombieReport implements Countable
 
     function get_parameters()
     {
-        
+
         $result = array(
             'name' => 'zombie_report_parameters',
             'method' => 'GET',
@@ -149,7 +149,7 @@ class ZombieReport implements Countable
     {
 
         /**
-         * todo check token 
+         * todo check token
          */
         $check = Security::check_token('post');
         Security::clear_token();
@@ -197,7 +197,7 @@ class ZombieReport implements Countable
 
         $ceiling = $this->get_ceiling();
         $active_only = $this->get_active_only();
-        $items = ZombieManager::list_zombies($ceiling, $active_only);
+        $items = ZombieManager::listZombies($ceiling, $active_only);
         return count($items);
     }
 
@@ -209,7 +209,7 @@ class ZombieReport implements Countable
 
         $ceiling = $this->get_ceiling();
         $active_only = $this->get_active_only();
-        $items = ZombieManager::list_zombies($ceiling, $active_only)->limit($count, $from)->orderby($column, $direction);
+        $items = ZombieManager::listZombies($ceiling, $active_only, $count, $from, $column, $direction);
         $result = array();
         foreach ($items as $item) {
             $row = array();
@@ -231,7 +231,6 @@ class ZombieReport implements Countable
 
     function display_data($return = false)
     {
-
         $count = array($this, 'count');
         $data = array($this, 'get_data');
 
@@ -277,9 +276,9 @@ class ZombieReport implements Countable
 
     /**
      * Table formatter for the active column.
-     * 
-     * @param string $active 
-     * @return string 
+     *
+     * @param string $active
+     * @return string
      */
     function format_active($active)
     {
@@ -323,4 +322,4 @@ class ZombieReport implements Countable
         }
     }
 
-}
\ No newline at end of file
+}