jack russell is the starhub's commeriial that dog loh.. sparky..
hee.
well, my dog is v cute, i didnt train her, but somehow she dun pee
at home one. She will only relieve herself when she is out,
therefore we have to bring her out for walkie everyday, twice daily
in order for her to do her big and small business. there was a few
times whereby we found her entering the toilet to relieve herself,
and it was really surprising cos' we didnt train her at all.
However, i think becos the toilet's floor is wet, and therefore she
doesnt really dare to enter, and at time, she relieves herself just
at the door of the toilet, but not in the toilet.. but overall, she
is really easy to handle becos she doesnt gives us problems..
i think you are buy those potty trainning aids and follow those
instructions to train your dog. and then, another alternative that
my fren used to train her JRT is that when her dog pee, she use a
tissue to clean up, and then place the tissue at the newspaper
corner. the dog will somehow smell it, and after sometime, she will
relieve herself at that spot. Just that easy 
All e best in trainning your dog!!
btw, i have read somewhere that when u are trainning your dog, dun
scold or beat it if you realised them dirtying the hse with their
faeces if you didnt catch them doing it at that moment. That means,
if you realise there is urine on the floor only 5 min after he/she
pee, dun scold her. she have most prob forgotten that she has pee
jus now, and her scoldings might be responding to her that the
thing that she is doing exactly at the time where u scold her is
wrong. in another words, scold her only if you catch her/him
dirtying the hse at that instant.