Lusin type theorems for Radon measures

We add to the literature the following observation. If µ is a singular measure on ℝn which assigns measure zero to every porous set and f ℝn → ℝ is a Lipschitz function which is non-differentiable -a.e., then for every C1 function g:ℝn → ℝ it holds (Formula Presented). In other words the Lusin type approximation property of Lipschitz functions with C1 functions does not hold with respect to a general Radon measure.