trying to log all bad logins

[pattycake]

I have a lot of people telling me that their logins are not working, and it's usually a user error.

But, to be sure, I would like to log all bad login requests

In login.php

if (!verify_authentication($vbulletin->GPC['vb_login_username'], $vbulletin->GPC['vb_login_password'], $vbulletin->GPC['vb_login_md5password'], $vbulletin->GPC['vb_login_md5password_utf'], $vbulletin->GPC['cookieuser'], true))
	{

Inside the above loop, I tried setting these variables so I could later write them out to a log file.

$tried_username=$vbulletin->GPC['vb_login_username'];
$tried_password=$vbulletin->GPC['vb_login_password'];

$tried_username works.. it's capturing what they entered but, $tried_password is always blank.

What I am doing wrong?