[jQuery] background mouseover fade effect

I need to add a mouseover effect to the navigation for a site that I'm
building.  I need the backgroundColor to fade from none, to black, and
then on mouseout, I need it to fade back to none.  This would be easy
if I were using two colors, but since I'm using 'none' as one of the
color's, I don't know what to do.  I have tried:

[code]
$('.nav_link').hover(function() {
    $(this).animate({backgroundColor: '#000000'});
}, function() {
    $(this).animate({backgroundColor: 'none'});
});
[/code]

but that doesn't seem to work.

Any help / plugin links would be greatly appreciated.

Thanks, bye.