Oh, Nad, how silly! The only thing I can remotely connect to what that person was saying is that after the baby is born, they will probably rub your stomach to make the contractions continue & expel the placenta. But that's "kneading"...it's done pretty hard and it's done in conjunction with contractions that are already occuring. I have NEVER heard of a woman going into labor from rubbing. In fact, women do a million different things to get labor going and AREN'T successful. Even orgasm...which does in fact produce contractions...won't make a labor start until the baby is very ready (except if you've been restricted from it).
I wouldn't worry. Rub away! I rubbed all the time during my pregnancy. Colin was born just one day before his due date. :)