Translate Theme My Login pt_BR

Hi all,
I want to translate to pt_BR the “Theme My Login” plugin. This plugin has a laguage folder that is used to put the translated .po and .mo files. But, it doesn’t recognize them.

The “theme-my-login.php”, located in root folder of the plugin, have this line to load lang files:

load_plugin_textdomain('theme-my-login', '', plugin_basename(dirname(__FILE__) . '/language'));

Here are the lines I want to translate, inside theme-my-login.php:

$title = sprintf(__('Welcome, %s', 'theme-my-login'), $user->display_name);
$title = __('Register', 'theme-my-login');

This is the content of language folder

# ls -l /usr/share/wordpress/wp-content/plugins/theme-my-login/language/
-rw-r--r-- 1 www-data www-data 418 2010-02-16 11:25 theme-my-login.mo
-rw-r--r-- 1 www-data www-data 545 2010-02-16 11:25 theme-my-login.pot
-rw-r--r-- 1 www-data www-data 514 2010-02-16 11:25 theme-my-login-pt_BR.mo
-rw-r--r-- 1 www-data www-data 586 2010-02-16 11:25 theme-my-login-pt_BR.po

This is the content of theme-my-login.pot

msgid ""
msgstr ""
"Project-Id-Version: Theme My Login 4.4\n"
"Report-Msgid-Bugs-To: \n"
"POT-Creation-Date: 2010-02-16 11:58+0100\n"
"PO-Revision-Date: \n"
"Last-Translator: \n"
"Language-Team: None\n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"
"X-Poedit-SourceCharset: utf-8\n"
"X-Poedit-KeywordsList: __;_re;_e\n"
"X-Poedit-Basepath: .\n"
"X-Poedit-SearchPath-0: ..\n"

#: ../theme-my-login.php:550
msgid "Welcome"
msgstr ""

#: ../theme-my-login.php:554
msgid "Register"
msgstr ""

This is the content of theme-my-login-pt_BR.po

msgid ""
msgstr ""
"Project-Id-Version: Theme My Login 4.4\n"
"Report-Msgid-Bugs-To: \n"
"POT-Creation-Date: 2010-02-16 11:58+0100\n"
"PO-Revision-Date: \n"
"Last-Translator: \n"
"Language-Team: None\n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"
"X-Poedit-Language: pt_BR\n"
"X-Poedit-Country: Brazil\n"
"X-Poedit-Basepath: .\n"
"X-Poedit-KeywordsList: _r;_re;__\n"
"X-Poedit-SearchPath-0: .\n"

#: ../theme-my-login.php:550
msgid "Welcome"
msgstr "Bem Vindo"

#: ../theme-my-login.php:554
msgid "Register"
msgstr "Registrar"