[FrogMouth]

This situation happend to me in Vegas a couple months ago.

Final Table ~5 players:

Fold, MP raises 3x bb, fold, fold, Me in BB w/ATs

What struck me as odd was MP was semi short, and had been open pushing all night, and I made mention to the fact that he now just raised.

I sit back in my chair and think for a moment (I had him covered 3-1). In my head I'm thinking I'm playing for all his chips, and I'm sure he was thinking the same. I loudly announce call and he filps his cards showing 77 and starts to push the rest of his chips in. Table goes nuts, dealer makes him take his chips back leving the PFR, and deals the flop. While no official penalty, he has the unfortuante pleasure of me knowing his hole cards the rest of the (short) hand.

In your situation, SB didn't announce raise or all in, & he moved his chips to the middle. I don't see how that can be considered anything other than a call. Exposing his hand benifits no one but his opponent.

Put it this way, "let's do it!' doesn't mean hes folding. Call plain and simple.