Advenures in Potty Training

I have a three year old and we have been potty training for the last month.  First let me say that I think that "training" is a funny term.  If anyone is training anyone, your child is training you.  Be that as it may, we are potty "training".  I have tried to make my child potty in the potty many times starting around his 2nd birthday, each time unsuccessful.  In December, it was his time and he started to pee! it was awesome and easy once he was ready.  HOWEVER; I am having the hardest time with poop.  I know he knows the sensation because he hides in his room until he is done pooping and then tells me he has to potty.  I am not sure if he knows how to poop though.  It is still frustrating though.