Post moved to the top (originally posted on April 23) because there's a new comment:
An interesting paper by Otávio Bueno entitled "Relativism and Scepticism" has just appeared in the International Journal of Philosophical Studies. It forms part of a book symposium on Steven Hales' Relativism and the Foundations of Philosophy. I think that Otávio's interpretation of the dialectical character of Pyrrhonism is entirely correct. You can find his paper here.