Because no way is calling correct.
Party Poker 0.50/1 Hold'em (9 handed)
converter
Preflop: Hero is MP1 with 6[img]/images/graemlins/spade.gif[/img], A[img]/images/graemlins/spade.gif[/img].
<font color="#666666">
1 fold</font>, UTG+1 calls, Hero calls, <font color="#666666">
1 fold</font>, MP3 calls, CO calls, <font color="#666666">
1 fold</font>, SB completes, BB checks.
Flop: (6 SB) T[img]/images/graemlins/club.gif[/img], J[img]/images/graemlins/diamond.gif[/img], 6[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(6 players)</font>
SB checks, BB checks, <font color="#CC3333">UTG+1 bets</font>, Hero ?