You're right - same names can cause a problem and having a unique id would solve it. What you end up having to do is have the key of the associative array (also known as a hash) be the unique ID (which doesn't necessarily have to be a number, though usually is) and the value be a reference to the data structure for that unique id.

However, like all solutions, I would make sure that you actually have the problem before implementing a solution that causes your code to become more complex. If you had two Jim Jones, I'd make sure to change it to Jim A. Jones and Jim B. Jones. Remember, you have to relate this back to your own life. So, something like "Jim Jones (college)" and "Jim Jones (work)" can also be used without having to change the code. :-)

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We are the carpenters and bricklayers of the Information Age.

The idea is a little like C++ templates, except not quite so brain-meltingly complicated. -- TheDamian, Exegesis 6

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.