Dear Umashankar You have gone off-tangent.I am not contesting any smrthis or the veracity of Vyasa or Parasara.The question was when and how the caste system started?.we see from the puranas that the castes were formed by varnasankara.That is all.You can read the Brahmavaivartapurana which was also compiled by Vyasa. N.Srikanta.