Joomla 3.1.x: ini_set() has been disabled for security reasons (old)

When I open my web using Joomla version 3.1x, I found annoying messages "ini_set() has been disabled for security reasons". Unfortunately, this warning prevent me to login into Joomla administration.

There are 2 way to fix it. You can choose one of these way:

1. You can edit [your root Joomla]/configuration..php

and add

error_reporting(0);
@ini_set(‘display_errors’, 0);

between <?php and class JConfig

it's become like this

<?php
error_reporting(0);
@ini_set(‘display_errors’, 0);

class JConfig {

2. or you can edit file [your root Joomla]/libraries/joomla/session/session.php and add @ in every ini_set command.

For Example in line 120 (line number may deferent for each Joomla version) it becomes like this.

@ini_set('session.use_trans_sid', '0');

done.... :)