use database manager in db session driver.

system/session/db.php

@@ -1,6 +1,7 @@
 <?php namespace System\Session;
 
 use System\Config;
+use System\DB\Manager;
 
 class DB implements Driver {
 
@@ -62,7 +63,7 @@ public function sweep($expiration)
 	 */
 	private function table()
 	{
-		return \System\DB::table(Config::get('session.table'));		
+		return Manager::connection()->table(Config::get('session.table'));		
 	}
 	
 }