Khinchin theorem for interval exchange transformations

We define a diophantine condition for interval exchange transformations (i.e.t.). When the number of intervals is two, that is for rotations on the circle, our condition coincides with the one in the classical Khinchin theorem, modulo the identification of a rotation with its rotation number. We prove that for i.e.t.s we have the same dichotomy of Khinchin theorem