populate form input option dropdown box from existing data

I am having difficulties figuring out how enter retrieved data into a
dropdown box for editing. Here's a snippet:
...snip
<select name="categoriesIN[]" multiple size="8">
        <option value="1">Civilization</option>
        <option value="2">Monuments, Temples &amp; Tombs</option>
        <option value="3">Pharaohs and Queens</option>... snip

As I understand it, I need to put an array ( $categoriesIN[] ) somewhere
in the above code... or do I need to insert a series of value "selected"
fields for the values?
The closest thing to what I need, seems to be in this post:
http://www.hpfreaks.com/forums/index.php?topic=165215
But it doesn't appear too inviting... not sure if they ever got it to
work...

-- 
Hervé Kempf: "Pour sauver la planète, sortez du capitalisme."
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Phil Jourdan --- [email protected]
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