BuddyPress.org

thanks @DJPaul ,

somehow I missed this plugin. Yes, it includes two very good plugins, unfortunatelly, bp translate is left without support, but first, what I am faced with after activation is some mistake with flags path “Incorrect Flag Image Path! Please correct it!”.
if someone will try this plugin too, I have WPMU 3.0.3 + BP 1.2.6.

actually, this is quite interesting, how bp translate could work successfully, when latest qtranslate breaks almost all bp pages, RSS etc.?!