Mahjong same games over and over.

I frequently play Mahjong on my Ubuntu Linux 12.04 system, and I had the same problem in previous sysems. I start a game and notice that the tiles are all in the same position as I played earlier in the day. I click on "New Game" but it's the same games that keep coming up over and over. It is frustrating that the program doesn't mix the tiles when so many combinations must be possible. It's really annoying and boring when I realise that I played this game yesterday with all the tiles in the same places.