Boolean modifier not working in 2.57b?

I’m a new user, just learning my way.

I have both 2.49b and 2.57b.

This boolean mesh split technique using boolean tool W key works fine in 2.49b.

However there seems to be no direct tool equivlent in 2.57b and you have to use the boolean modifier, but whateverway I try to emulate the same mesh split does not work.

Any clues? Or is this broken in 2.57?


worked ok, when i solidified the plain.

Thanks for the reply. How do I do that?