[Plugin: SimpleMap Store Locator] Is language support working?

I already define
define(‘WPLANG’, ‘pt_BR’);
and tried
define (‘WPLANG’, ‘es_ES’);
but nothing seems to work on simple map.

Lang folder exists with default *.mo and *.po files
I don´t have WPML installed.
Any tip?

http://ww.wp.xz.cn/extend/plugins/simplemap/