[Plugin: User Access Manager] How i can change language?

Hi, i have installed UAM 1.2.2 on WP 3.2.1.

This plugin is awesome and works great, but i have a problem. In “lang” directory there is a spanish translation for the plugin, but how can i activate it???

Thanks!

http://ww.wp.xz.cn/extend/plugins/user-access-manager/