diff --git a/src/mibew/install/migrate.php b/src/mibew/install/migrate.php
index 071e155e..2dda441f 100644
--- a/src/mibew/install/migrate.php
+++ b/src/mibew/install/migrate.php
@@ -17,7 +17,7 @@
 
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 
-$db = Database::getInstance();
+$db = \Mibew\Database::getInstance();
 
 $db->throwExeptions(true);
 
diff --git a/src/mibew/libs/canned.php b/src/mibew/libs/canned.php
index 603e1678..4b9ac1c7 100644
--- a/src/mibew/libs/canned.php
+++ b/src/mibew/libs/canned.php
@@ -15,6 +15,9 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
 function load_canned_messages($locale, $groupid)
 {
 	$db = Database::getInstance();
diff --git a/src/mibew/libs/chat.php b/src/mibew/libs/chat.php
index 5cb6d3a0..c2f305cf 100644
--- a/src/mibew/libs/chat.php
+++ b/src/mibew/libs/chat.php
@@ -16,6 +16,7 @@
  */
 
 // Import namespaces and classes of the core
+use Mibew\Database;
 use Mibew\Settings;
 
 // Initialize libraries
diff --git a/src/mibew/libs/classes/database.php b/src/mibew/libs/classes/Mibew/Database.php
similarity index 92%
rename from src/mibew/libs/classes/database.php
rename to src/mibew/libs/classes/Mibew/Database.php
index 7180be97..624ded5c 100644
--- a/src/mibew/libs/classes/database.php
+++ b/src/mibew/libs/classes/Mibew/Database.php
@@ -15,6 +15,8 @@
  * limitations under the License.
  */
 
+namespace Mibew;
+
 /**
  * Encapsulates work with database. Implenets singleton pattern to provide only
  * one instance.
@@ -35,7 +37,7 @@ Class Database{
 
 	/**
 	 * PDO object
-	 * @var PDO
+	 * @var \PDO
 	 */
 	protected $dbh = NULL;
 
@@ -155,16 +157,16 @@ Class Database{
 	public static function initialize($host, $user, $pass, $use_pconn, $db, $prefix, $force_charset = false, $encoding = 'utf8') {
 		// Check PDO
 		if (! extension_loaded('PDO')) {
-			throw new Exception('PDO extension is not loaded');
+			throw new \Exception('PDO extension is not loaded');
 		}
 
 		if (! extension_loaded('pdo_mysql')) {
-			throw new Exception('pdo_mysql extension is not loaded');
+			throw new \Exception('pdo_mysql extension is not loaded');
 		}
 
 		// Check if initialization
 		if (! is_null(self::$instance)) {
-			throw new Exception('Database already initialized');
+			throw new \Exception('Database already initialized');
 		}
 
 		// Create database instance
@@ -181,11 +183,11 @@ Class Database{
 		$instance->usePersistentConnection = $use_pconn;
 
 		// Create PDO object
-		$instance->dbh = new PDO(
+		$instance->dbh = new \PDO(
 			"mysql:host={$instance->dbHost};dbname={$instance->dbName}",
 			$instance->dbLogin,
 			$instance->dbPass,
-			array(PDO::ATTR_PERSISTENT => $instance->usePersistentConnection)
+			array(\PDO::ATTR_PERSISTENT => $instance->usePersistentConnection)
 		);
 
 		if ($instance->forceCharsetInConnection) {
@@ -208,9 +210,9 @@ Class Database{
 
 	/**
 	 * Handles errors
-	 * @param Exception $e
+	 * @param \Exception $e
 	 */
-	protected function handleError(Exception $e){
+	protected function handleError(\Exception $e){
 		if ($this->throwExceptions) {
 			throw $e;
 		}
@@ -299,7 +301,7 @@ Class Database{
 			// Check if error occurs
 			if ($this->preparedStatements[$query_key]->errorCode() !== '00000') {
 				$errorInfo = $this->preparedStatements[$query_key]->errorInfo();
-				throw new Exception(' Query failed: ' . $errorInfo[2]);
+				throw new \Exception(' Query failed: ' . $errorInfo[2]);
 			}
 
 			// No need to return rows
@@ -315,16 +317,16 @@ Class Database{
 			}
 			switch($params['fetch_type']){
 				case Database::FETCH_NUM:
-					$fetch_type = PDO::FETCH_NUM;
+					$fetch_type = \PDO::FETCH_NUM;
 					break;
 				case Database::FETCH_ASSOC:
-					$fetch_type = PDO::FETCH_ASSOC;
+					$fetch_type = \PDO::FETCH_ASSOC;
 					break;
 				case Database::FETCH_BOTH:
-					$fetch_type = PDO::FETCH_BOTH;
+					$fetch_type = \PDO::FETCH_BOTH;
 					break;
 				default:
-					throw new Exception("Unknown 'fetch_type' value!");
+					throw new \Exception("Unknown 'fetch_type' value!");
 			}
 
 			// Get results
@@ -334,12 +336,12 @@ Class Database{
 			} elseif ($params['return_rows'] == Database::RETURN_ALL_ROWS) {
 				$rows = $this->preparedStatements[$query_key]->fetchAll($fetch_type);
 			} else {
-				throw new Exception("Unknown 'return_rows' value!");
+				throw new \Exception("Unknown 'return_rows' value!");
 			}
 			$this->preparedStatements[$query_key]->closeCursor();
 
 			return $rows;
-		} catch(Exception $e) {
+		} catch(\Exception $e) {
 			$this->handleError($e);
 		}
 	}
@@ -348,7 +350,7 @@ Class Database{
 	 * Returns value of PDOStatement::$errorInfo property for last query
 	 * @return string Error info array
 	 *
-	 * @see PDOStatement::$erorrInfo
+	 * @see \PDOStatement::$erorrInfo
 	 */
 	public function errorInfo(){
 		if (is_null($this->lastQuery)) {
@@ -356,7 +358,7 @@ Class Database{
 		}
 		try{
 			$errorInfo = $this->preparedStatements[$this->lastQuery]->errorInfo();
-		} catch (Exception $e) {
+		} catch (\Exception $e) {
 			$this->handleError($e);
 		}
 		return $errorInfo;
@@ -370,7 +372,7 @@ Class Database{
 	public function insertedId(){
 		try{
 			$lastInsertedId = $this->dbh->lastInsertId();
-		} catch(Exception $e) {
+		} catch(\Exception $e) {
 			$this->handleError($e);
 		}
 		return $lastInsertedId;
@@ -387,7 +389,7 @@ Class Database{
 		}
 		try{
 			$affected_rows =  $this->preparedStatements[$this->lastQuery]->rowCount();
-		} catch(Exception $e) {
+		} catch(\Exception $e) {
 			$this->handleError($e);
 		}
 		return $affected_rows;
diff --git a/src/mibew/libs/classes/Mibew/Settings.php b/src/mibew/libs/classes/Mibew/Settings.php
index a04e5ed5..517683a0 100644
--- a/src/mibew/libs/classes/Mibew/Settings.php
+++ b/src/mibew/libs/classes/Mibew/Settings.php
@@ -17,9 +17,6 @@
 
 namespace Mibew;
 
-// Import namespaces and classes of the core
-use \Database;
-
 /**
  * Encapsulates work with system settings.
  */
diff --git a/src/mibew/libs/classes/client_side_processor.php b/src/mibew/libs/classes/client_side_processor.php
index 9585e685..290c5b35 100644
--- a/src/mibew/libs/classes/client_side_processor.php
+++ b/src/mibew/libs/classes/client_side_processor.php
@@ -15,6 +15,9 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
 /**
  * Base class for all request processors that interact with JavaScript
  * applications at the client side.
diff --git a/src/mibew/libs/classes/request_processor.php b/src/mibew/libs/classes/request_processor.php
index 8f6b64fc..0e31fe6c 100644
--- a/src/mibew/libs/classes/request_processor.php
+++ b/src/mibew/libs/classes/request_processor.php
@@ -15,6 +15,9 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
 /**
  * Implements abstract class for request processing
  *
diff --git a/src/mibew/libs/classes/thread.php b/src/mibew/libs/classes/thread.php
index f249f4d8..81340fb0 100644
--- a/src/mibew/libs/classes/thread.php
+++ b/src/mibew/libs/classes/thread.php
@@ -16,6 +16,7 @@
  */
 
 // Import namespaces and classes of the core
+use Mibew\Database;
 use Mibew\Settings;
 
 /**
diff --git a/src/mibew/libs/classes/users_processor.php b/src/mibew/libs/classes/users_processor.php
index 340e9824..fb780a6a 100644
--- a/src/mibew/libs/classes/users_processor.php
+++ b/src/mibew/libs/classes/users_processor.php
@@ -16,6 +16,7 @@
  */
 
 // Import namespaces and classes of the core
+use Mibew\Database;
 use Mibew\Settings;
 
 /**
diff --git a/src/mibew/libs/groups.php b/src/mibew/libs/groups.php
index 8db0e9de..7a72dd67 100644
--- a/src/mibew/libs/groups.php
+++ b/src/mibew/libs/groups.php
@@ -16,6 +16,7 @@
  */
 
 // Import namespaces and classes of the core
+use Mibew\Database;
 use Mibew\Settings;
 
 function group_by_id($id)
diff --git a/src/mibew/libs/init.php b/src/mibew/libs/init.php
index 52472fa9..9693ed13 100644
--- a/src/mibew/libs/init.php
+++ b/src/mibew/libs/init.php
@@ -37,7 +37,6 @@ require_once(MIBEW_FS_ROOT.'/libs/common/autoload.php');
 spl_autoload_register('class_autoload');
 
 // Include system classes
-require_once(MIBEW_FS_ROOT.'/libs/classes/database.php');
 require_once(MIBEW_FS_ROOT.'/libs/classes/event_dispatcher.php');
 require_once(MIBEW_FS_ROOT.'/libs/classes/plugin_manager.php');
 require_once(MIBEW_FS_ROOT.'/libs/classes/plugin.php');
@@ -66,7 +65,7 @@ if (is_secure_request()) {
 session_start();
 
 // Initialize the database
-Database::initialize(
+\Mibew\Database::initialize(
 	$mysqlhost,
 	$mysqllogin,
 	$mysqlpass,
diff --git a/src/mibew/libs/invitation.php b/src/mibew/libs/invitation.php
index 07dd8196..7be20eb6 100644
--- a/src/mibew/libs/invitation.php
+++ b/src/mibew/libs/invitation.php
@@ -16,6 +16,7 @@
  */
 
 // Import namespaces and classes of the core
+use Mibew\Database;
 use Mibew\Settings;
 
 /**
diff --git a/src/mibew/libs/operator.php b/src/mibew/libs/operator.php
index 8c4c8a94..182acfc6 100644
--- a/src/mibew/libs/operator.php
+++ b/src/mibew/libs/operator.php
@@ -16,6 +16,7 @@
  */
 
 // Import namespaces and classes of the core
+use Mibew\Database;
 use Mibew\Settings;
 
 /**
diff --git a/src/mibew/libs/pagination.php b/src/mibew/libs/pagination.php
index 4c08a2ee..247cca7c 100644
--- a/src/mibew/libs/pagination.php
+++ b/src/mibew/libs/pagination.php
@@ -15,6 +15,9 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
 $pagination_spacing = "   ";
 $links_on_page = 5;
 
@@ -82,9 +85,9 @@ function setup_pagination($items, $default_items_per_page = 15)
  * @param string $order Order clause
  * @param string $countfields Field, substituted in SQL COUNT function
  * @param array $values Associative array of substituted values. Keys are named placeholders in the 
- *   query(see Database::query() and its $values parameter description)
+ *   query(see \Mibew\Database::query() and its $values parameter description)
  * 
- * @see Database::query()
+ * @see \Mibew\Database::query()
  */
 function select_with_pagintation($fields, $table, $conditions, $order, $countfields, $values)
 {
diff --git a/src/mibew/libs/statistics.php b/src/mibew/libs/statistics.php
index 1ba2cd56..ab03a434 100644
--- a/src/mibew/libs/statistics.php
+++ b/src/mibew/libs/statistics.php
@@ -16,6 +16,7 @@
  */
 
 // Import namespaces and classes of the core
+use Mibew\Database;
 use Mibew\Settings;
 
 function get_statistics_query($type)
diff --git a/src/mibew/libs/track.php b/src/mibew/libs/track.php
index 29c77945..4aa8f487 100644
--- a/src/mibew/libs/track.php
+++ b/src/mibew/libs/track.php
@@ -16,6 +16,7 @@
  */
 
 // Import namespaces and classes of the core
+use Mibew\Database;
 use Mibew\Settings;
 
 // Initialize libraries
diff --git a/src/mibew/operator/ban.php b/src/mibew/operator/ban.php
index af924ba6..cd7da435 100644
--- a/src/mibew/operator/ban.php
+++ b/src/mibew/operator/ban.php
@@ -15,6 +15,10 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
+// Initialize libraries
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 require_once(MIBEW_FS_ROOT.'/libs/chat.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator.php');
diff --git a/src/mibew/operator/blocked.php b/src/mibew/operator/blocked.php
index bd6f8800..7818c12d 100644
--- a/src/mibew/operator/blocked.php
+++ b/src/mibew/operator/blocked.php
@@ -15,6 +15,10 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
+// Initialize libraries
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 require_once(MIBEW_FS_ROOT.'/libs/chat.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator.php');
diff --git a/src/mibew/operator/canned.php b/src/mibew/operator/canned.php
index 3a57d774..883955fa 100644
--- a/src/mibew/operator/canned.php
+++ b/src/mibew/operator/canned.php
@@ -15,6 +15,10 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
+// Initialize libraries
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 require_once(MIBEW_FS_ROOT.'/libs/canned.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator.php');
diff --git a/src/mibew/operator/group.php b/src/mibew/operator/group.php
index c811db9b..8a69582d 100644
--- a/src/mibew/operator/group.php
+++ b/src/mibew/operator/group.php
@@ -15,6 +15,10 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
+// Initialize libraries
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator.php');
 require_once(MIBEW_FS_ROOT.'/libs/groups.php');
diff --git a/src/mibew/operator/groupmembers.php b/src/mibew/operator/groupmembers.php
index 93da0559..6d2c84d1 100644
--- a/src/mibew/operator/groupmembers.php
+++ b/src/mibew/operator/groupmembers.php
@@ -15,6 +15,10 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
+// Initialize libraries
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator.php');
 require_once(MIBEW_FS_ROOT.'/libs/groups.php');
diff --git a/src/mibew/operator/groups.php b/src/mibew/operator/groups.php
index e1aaf543..dd991d55 100644
--- a/src/mibew/operator/groups.php
+++ b/src/mibew/operator/groups.php
@@ -16,6 +16,7 @@
  */
 
 // Import namespaces and classes of the core
+use Mibew\Database;
 use Mibew\Settings;
 
 // Initialize libraries
diff --git a/src/mibew/operator/history.php b/src/mibew/operator/history.php
index e76e5b6b..e137b906 100644
--- a/src/mibew/operator/history.php
+++ b/src/mibew/operator/history.php
@@ -15,6 +15,10 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
+// Initialize libraries
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator.php');
 require_once(MIBEW_FS_ROOT.'/libs/chat.php');
diff --git a/src/mibew/operator/operators.php b/src/mibew/operator/operators.php
index c0d80f92..640fa1cb 100644
--- a/src/mibew/operator/operators.php
+++ b/src/mibew/operator/operators.php
@@ -15,6 +15,10 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
+// Initialize libraries
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator.php');
 require_once(MIBEW_FS_ROOT.'/libs/interfaces/style.php');
diff --git a/src/mibew/operator/opgroups.php b/src/mibew/operator/opgroups.php
index aadb89bf..115f12a5 100644
--- a/src/mibew/operator/opgroups.php
+++ b/src/mibew/operator/opgroups.php
@@ -15,6 +15,10 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
+// Initialize libraries
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator_settings.php');
diff --git a/src/mibew/operator/redirect.php b/src/mibew/operator/redirect.php
index aae2acef..39198c85 100644
--- a/src/mibew/operator/redirect.php
+++ b/src/mibew/operator/redirect.php
@@ -15,6 +15,10 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
+// Initialize libraries
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator.php');
 require_once(MIBEW_FS_ROOT.'/libs/chat.php');
diff --git a/src/mibew/operator/resetpwd.php b/src/mibew/operator/resetpwd.php
index 7238f5e9..d5add122 100644
--- a/src/mibew/operator/resetpwd.php
+++ b/src/mibew/operator/resetpwd.php
@@ -15,6 +15,10 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
+// Initialize libraries
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator.php');
 require_once(MIBEW_FS_ROOT.'/libs/settings.php');
diff --git a/src/mibew/operator/restore.php b/src/mibew/operator/restore.php
index 614ef678..ed2ba094 100644
--- a/src/mibew/operator/restore.php
+++ b/src/mibew/operator/restore.php
@@ -15,6 +15,10 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
+// Initialize libraries
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator.php');
 require_once(MIBEW_FS_ROOT.'/libs/settings.php');
diff --git a/src/mibew/operator/statistics.php b/src/mibew/operator/statistics.php
index 5312eeb1..67096b6c 100644
--- a/src/mibew/operator/statistics.php
+++ b/src/mibew/operator/statistics.php
@@ -16,6 +16,7 @@
  */
 
 // Import namespaces and classes of the core
+use Mibew\Database;
 use Mibew\Settings;
 
 // Initialize libraries
diff --git a/src/mibew/operator/threadprocessor.php b/src/mibew/operator/threadprocessor.php
index 9fdd1215..0225781f 100644
--- a/src/mibew/operator/threadprocessor.php
+++ b/src/mibew/operator/threadprocessor.php
@@ -15,6 +15,10 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
+// Initialize libraries
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator.php');
 require_once(MIBEW_FS_ROOT.'/libs/chat.php');
diff --git a/src/mibew/operator/userhistory.php b/src/mibew/operator/userhistory.php
index 46681112..3b471f84 100644
--- a/src/mibew/operator/userhistory.php
+++ b/src/mibew/operator/userhistory.php
@@ -15,6 +15,10 @@
  * limitations under the License.
  */
 
+// Import namespaces and classes of the core
+use Mibew\Database;
+
+// Initialize libraries
 require_once(dirname(dirname(__FILE__)).'/libs/init.php');
 require_once(MIBEW_FS_ROOT.'/libs/operator.php');
 require_once(MIBEW_FS_ROOT.'/libs/chat.php');