[Theme: Brand New Day] Language changes?

Actually, I have got my WordPress on spanish, but I can’t use the translation files for your theme.
This is the line added to wp-config.php:
define ('WPLANG', 'es_ES');
And the translation files of the theme are named es_ES.mo and es_ES.po
This is the content of es_ES.po:

msgid ""
msgstr ""
"Project-Id-Version: Brand New Day 1.0\n"
"Report-Msgid-Bugs-To: \n"
"POT-Creation-Date: 2011-10-14 18:58-0500\n"
"PO-Revision-Date: 2011-10-14 18:58-0500\n"
"Last-Translator: Luis Lammel <kamelarg@gmail.com>\n"
"Language-Team: \n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"
"X-Poedit-KeywordsList: __;gettext;gettext_noop;_e;esc_attr_e\n"
"X-Poedit-Basepath: .\n"
"X-Poedit-SearchPath-0: .\n"
"X-Poedit-SearchPath-1: ..\n"

#: ../comments.php:9
msgid "This post is password protected. Enter the password to view comments."
msgstr "Este artículo se encuentra protegido bajo contraseña. Por favor, ingrese la clave para ver los comentarios."

#: ../comments.php:19
msgid "No Responses"
msgstr "No hay respuestas"

#: ../comments.php:19
msgid "One Response"
msgstr "Una respuesta"

#: ../comments.php:19
msgid "Responses"
msgstr "respuestas"

#: ../comments.php:19
msgid "to"
msgstr "hasta"

#: ../comments.php:42
msgid "Comments are closed."
msgstr "Los comentarios fueron bloqueados por el administrador."

#: ../footer.php:21
msgid "Brand New Day Theme by Caroline Moore"
msgstr "Tema: Brand New Day por Caroline Moore"

#: ../footer.php:22
msgid "Copyright"
msgstr "Copyright"

#: ../footer.php:23
msgid "Powered by"
msgstr "Blog hecho con: "

#: ../footer.php:23
msgid "WordPress"
msgstr "WordPress"

#: ../functions.php:54
#: ../sidebar.php:14
msgid "Vertical Sidebar"
msgstr "Barra lateral vertical"

#: ../functions.php:63
#: ../sidebar-footer1.php:8
msgid "Footer Sidebar 1"
msgstr "Barra lateral del pié nº1"

#: ../functions.php:71
#: ../sidebar-footer2.php:8
msgid "Footer Sidebar 2"
msgstr "Barra lateral del pié nº2"

#: ../functions.php:79
#: ../sidebar-footer3.php:8
msgid "Footer Sidebar 3"
msgstr "Barra lateral del pié nº3"

#: ../functions.php:87
#: ../sidebar-footer4.php:8
msgid "Footer Sidebar 4"
msgstr "Barra lateral del pié nº4"

#: ../index.php:13
msgid "You searched for"
msgstr "Se ha buscado"

#: ../index.php:24
#: ../index.php:32
msgid "Permanent Link to"
msgstr "Link Permanente hacia"

#: ../index.php:29
msgid "Edit"
msgstr "Editar"

#: ../index.php:33
#: ../single.php:18
msgid "by"
msgstr "por"

#: ../index.php:36
#: ../page-nosidebar.php:22
#: ../page.php:21
#: ../single.php:21
msgid "Read the rest of this entry"
msgstr "Leer el resto de la entrada"

#: ../index.php:39
#: ../page-nosidebar.php:24
#: ../page.php:23
#: ../single.php:23
msgid "Pages:"
msgstr "Páginas"

#: ../index.php:43
msgid "No Comments"
msgstr "No hay comentarios"

#: ../index.php:43
msgid "Comment"
msgstr "Comentar"

#: ../index.php:43
msgid "Comments"
msgstr "Comentarios"

#: ../index.php:50
msgid "Older Entries"
msgstr "Entradas anteriores"

#: ../index.php:51
msgid "Newer Entries"
msgstr "Entradas recientes"

#: ../index.php:56
#: ../single.php:39
msgid "Not Found"
msgstr "No encontrado"

#: ../index.php:57
#: ../single.php:40
msgid "Sorry, no posts matched your criteria."
msgstr "Disculpe, pero no hemos encontrado resultados que se ajusten a su criterio de búsqueda"

#: ../page-nosidebar.php:31
#: ../page.php:30
#: ../single.php:27
msgid "Edit this entry"
msgstr "Editar esta entrada"

#: ../searchform.php:8
msgid "Search:"
msgstr "Buscar:"

#: ../searchform.php:10
msgid "Go"
msgstr "IR"

#: ../single.php:18
msgid "on"
msgstr "el"

#: ../single.php:25
msgid "Posted in"
msgstr "Publicada el"

#: ../single.php:26
msgid "Tags:"
msgstr "Etiquetas:"

#: ../theme-options.php:17
#: ../theme-options.php:69
msgid "Theme Options"
msgstr "Opciones del tema"

#: ../theme-options.php:27
msgid "Daylight"
msgstr "Luz diurna"

#: ../theme-options.php:31
msgid "Nightlight"
msgstr "Luz nocturna"

#: ../theme-options.php:35
msgid "Winterlight"
msgstr "Luz invernal"

#: ../theme-options.php:39
msgid "Autumnlight"
msgstr "Luz otoñal"

#: ../theme-options.php:46
msgid "Right Sidebar"
msgstr "Barra lateral derecha"

#: ../theme-options.php:50
msgid "Left Sidebar"
msgstr "Barra lateral izquierda"

#: ../theme-options.php:54
msgid "No Sidebar"
msgstr "Sin barra lateral"

#: ../theme-options.php:72
msgid "Options saved"
msgstr "Opciones guardadas"

#: ../theme-options.php:86
#: ../theme-options.php:88
msgid "Theme Style"
msgstr "Estilo del tema"

#: ../theme-options.php:111
#: ../theme-options.php:113
msgid "Sidebar Options"
msgstr "Opciones de la barra lateral"

#: ../theme-options.php:134
msgid "Remove Search"
msgstr "Eliminar búsqueda"

#: ../theme-options.php:138
msgid "Remove search bar from header"
msgstr "Elimina la barra de búsqueda de la cabecera"

#: ../theme-options.php:148
msgid "Enable Simple Blog Mode"
msgstr "Habilitar modo simple del blog"

#: ../theme-options.php:152
msgid "Remove the sidebar, search bar and narrow the content column"
msgstr "Elimina la barra lateral, la barra de búsqueda y ensancha la columna de contenido"

#: ../theme-options.php:162
msgid "Custom CSS"
msgstr "CSS personalizado"

#: ../theme-options.php:166
msgid "Add any custom CSS rules here so they will persist through theme updates."
msgstr "Agrega cualquier regla personalizada de CSS, que se mantendrán aunque el tema sea actualizado."

#: ../theme-options.php:173
msgid "Save Options"
msgstr "Guardar opciones"

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