Again, the problem you experience seems to be specific to the Forum plugin. As far as I'm aware, Geeklog itself works reasonably well with RTL languages (and if it doesn't, please submit bug reports). So why don't you try working with the group that's trying to revive support for the Forum plugin by explaining to them exactly what's wrong and what needs to be fixed?

To answer your question: Text direction is changed automatically when the language file indicates that it's an RTL language by declaring this variable: $LANG_DIRECTION = 'rtl'; Everything else should happen automatically. And if it doesn't - see above.