https://bugs.freedesktop.org/show_bug.cgi?id=29137
--- Comment #6 from Marek Olšák maraeo@gmail.com 2010-08-02 07:40:17 PDT --- It won't certainly get fixed in r300g, we would have to reorder constants every draw call, which would incur noticable perfomance drop (in Gallium, constant buffers may be reused for several different shaders).
It might get fixed in the GLSL compiler, though, which resides in Mesa core. I'd rather wait until Intel merge their new GLSL compiler before looking into this issue.