Previous usernames

[gabrielfin]

I have searched, but didn't find anything.
I'm looking for a mod that stores all the usernames a user has ever had, and shows them in the profile. Is there anything like that?

[gabrielfin]

Nobody can help me? I know it's a simple mod, but I don't know where to write it. What I want to do, is a log with the display names each user has ever had.
In Profile.php, changed:

Koodi [Valitse] Laajenna

if (isset($_POST['realName']))
$profile_vars['realName'] = '\'' . $_POST['realName'] . '\'';

To:

Koodi [Valitse] Laajenna

if (isset($_POST['realName'])){
$profile_vars['realName'] = '\'' . $_POST['realName'] . '\'';
db_query("INSERT INTO {$db_prefix}log_usernames (member_id,name,date) VALUES ('$memID','$profile_vars[realName]','".time()."'", __FILE__, __LINE__);
   }

But it doesn't insert anything in the table. Could anyone help me?
It should actually be a very short simple code.
Thanks for any help.