To clarify:

This is what you see (I bet):

http://screenshotuploader.com/i/0Zo8znGtYTC.jpg

This is what I see:

http://screenshotuploader.com/i/zB7l57AFakm.jpg

Here you can see the likely source of the problem: the widget name is translated to "HTML libre" in the language pack.

http://screenshotuploader.com/i/iXTVoWLHXKM.jpg

same issue here: http://forums.b2evolution.net/viewtopic.php?t=21818

what the hell is wrong with the accented characters ?

If you have chaching turned on, you just need to wait for the cache to update.

@bit
Can you give me access to phpmyadmin?

Make sure you have the following settings in /conf/_locales.php

$evo_charset = '';
$force_io_charset_if_accepted = '';
$db_config['connection_charset'] = '';
$default_locale = 'en-US';

Check that you've set utf-8 charset for your custom locale
http://www.lalaurette.com.ar/blog/admin.php?ctrl=locales&action=edit&edit_locale=es-ES