I'm trying to do an integration with gravatar (http://www.gravatar.com), I'm follow these rules (http://en.gravatar.com/site/implement/url), but something strange happen...

I'm doing this way, in comment.class.php:

+ou- line 2218

$gravatar	= $this->censorText(JOSC_utils::filter($this->_item['email']));

+ou- line 2302

$gravatar	= md5(strtolower($gravatar));

$html 		= str_replace('{gravatar}', $gravatar, $html);

In my index template I put:
{gravatar}

OK so far...
But look, the md5 for my e-mail: ronildo@joomla.com.br is?
df858cc39c1f1ee9b167748b6c377335

But if I use this in a file php without Joomla:

<?php

$codigo=md5("ronildo@joomla.com.br");

echo($codigo);

?>

The md5 for my e-mail is:
bb6b3d2b065f0adde62551ad6d2df164 - And this one is the correct.

Any idea?