change my domain name

I had setup my wordpress mu on afraid.in and would now like to move it to gabruu.com, in my hosting account , i have allready change the hosting folder of gabruu.com to point to afraid.in, but can you please tell me how to rename the site from afraid.in to gabruu.com for all my subsites and primary site.

I have also added below lines in wp-config.php file .
define('WP_HOME','http://url.com/');
define('WP_SITEURL','http://url.com/')

but its not working.

Can anyone help plz.

Thank