There were five dice on the board - I had three and the carnival guy (oh hey Batista, he has a name!) had two. I guessed five fives and then his turn came and he guessed six fives.
Of course since there were only five dice on the board, I called his bluff and he did lose a die. As usual on my next turn the drop-down only let me choose up to four dice, which were all the ones left. So it's only letting him guess at extra dice.
Not really a big problem, I mean it did make it easier to spot his bluff so hey easier for me, but I'm guessing it's probably unintentional. <.<