Objects are supposed to be things that do stuff, not things that act as repositories. (Of course, there're exceptions to every rule, but it's a good starting point.) Now, there is a way to make a good configuration object. You just have to change the way you think about it.

What you could do is pass the configuration object a filename. You, as the main program, wouldn't know how the configuration file is set up or what all the things it specifies are. Then, what your main program would do is ask the object if XXX is set to nnn, maybe by doing something like

if ($config->isSet('XXX', nnn)) {
    # Do something here
} else {
    # Do something else here
}
[download]

------
We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.