How do I highlight parts of an imagemap on mouseover?

I tried to use ScottE's solution but unfortunately that meant adding the target image as a body background.

My solution is very close to his, but uses proper images

jQuery:

$(document).ready(function() {

    $(".map-areas area").mouseenter(function() {
        var idx = $(".map-areas area").index(this);
        $(".map-hovers img:eq(" + idx + ")").show();
        return false;
    });
    $(".map-hovers img").mouseleave(function() {
        $(".map-hovers img").hide();
        return false;
    });

});

The key concept here is that once you enter the map area, you show the map-hovers image, which then becomes your active layer under the mouse - Simply detecting when you leave that image is what make is smooth.

HTML: (almost the same, no need for trans image)

<div id="container">
        <img src="/images/full-map.png" width="220" height="238" class="map-trans" alt="Map / Carte" usemap="#region-map" />
        <div class="map-hovers">
            <img src="/images/map/sunset-country.png" alt="Sunset Country" />
            <img src="/images/map/north-of-superior.png" alt="North of Superior" />
            <img src="/images/map/algomas-country.png" alt="Algoma's Country" />
            <img src="/images/map/ontarios-wilderness.png" alt="Ontario's Wilderness" />
            <img src="/images/map/rainbow-country.png" alt="Rainbow Country" />
            <img src="/images/map/ontarios-near-north.png" alt="Ontario's Near North" />
            <img src="/images/map/muskoka.png" alt="Muskoka" />    
        </div>
</div>
    <map name="region-map" id="region-map" class="map-areas">
    <area shape="poly" coords="52,19,53,82,36,114,34,126,26,130,5,121,2,110,7,62" href="#d0" alt="Sunset Country" />
    <area shape="poly" coords="93,136,93,113,82,112,77,65,57,51,58,82,41,122,33,133,58,138,74,126" href="#d1" alt="No