Can't find the Physics + Dynamic toggle buttons

I’m running 2.49a and I have the book Mastering Blender in front of me. I’m currently on page 313 where it mentions enabling/disabling these button under the Logic panel, but I can’t can’t them. While the Dynamic button has probably become the Object type pull down menu, the Physics button seems to have vanished. Does anybody know where it is?

Is this of help http://blenderartists.org/forum/showthread.php?t=168214&page=1

I know why.
It’s because you haven’t got a world.
I had this problem.
Go to materials, click the WORLD tab, that looks like a globe.
add World

Thank you Richard, when I changed the Mist/Stars/Physics from bullet to none, the physics button showed up.