diff --git a/system/libraries/Session/Session.php b/system/libraries/Session/Session.php
index f250c3d..bf11cd1 100644
--- a/system/libraries/Session/Session.php
+++ b/system/libraries/Session/Session.php
@@ -122,7 +122,11 @@
 
 		session_start();
 
-		if (($regenerate_time = config_item('sess_time_to_update')) > 0)
+		// Is session ID auto-regeneration configured? (ignoring ajax requests)
+		if ( ! empty($_SERVER['HTTP_X_REQUESTED_WITH'])
+			&& strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) === 'xmlhttprequest'
+			&& $regenerate_time = config_item('sess_time_to_update')) > 0
+		)
 		{
 			if ( ! isset($_SESSION['__ci_last_regenerate']))
 			{