BuddyPress.org

I think more logical is to use WPLANG:

if ( file_exists( MUPLUGINDIR . ‘/bp-languages/buddypress-‘ . WPLANG . ‘.mo’ ) )

load_textdomain( ‘buddypress’, MUPLUGINDIR . ‘/bp-languages/buddypress-‘ . WPLANG . ‘.mo’ );

As my system locale is different.