Load translation for multisite failed

Hi.
The plugin doesn't use the language files in multisite installation.
The code in /wpmu_dev_maps_plugin.php line 40-44

if ( is_multisite() ) {
	load_muplugin_textdomain( AGM_LANG, false, AGM_PLUGIN_DIRNAME . '/languages/' );
} else {
	load_plugin_textdomain( AGM_LANG, false, AGM_PLUGIN_DIRNAME . '/languages/' );
}

forced the plugin to look at /mu-plugins/.. and not in /plugins/... for the language files.