dumbest. question. ever. - madden 360

i got madden about 2 weeks ago and i just finished my 1st season in franchise mode, but 1 stupid thing is REALLY bothering me....what buttons do you use for the high stepping/taunt run into the endzone thing. it's not in the instructions and i've always been able to figure it out in the other games, but i can't do it in '08. for awhile i wasn't even sure if it was in the game anymore, but a team i was playing did it this morning so it got me really irritated that i don't know how to do it

sorry for the pointless question, but of course there's some juicy karma for anyone that can tell me thank you!!