Either this program is going out of its way to disable (or change) backspace/delete or you have backspace/delete improperly configured and you just don't usually notice because your shell is going out of its way to deal with that.

The better way to read from <STDIN> is Term::ReadLine and friends. They allow you to edit what you type instead of just backspace/delete.

You might want to check "man stty" if you are on a Unix system.

        - tye (but my friends call me "Tye")