jquery tabs load event not firing

jquery tabs load event not firing

Hi, I'm using jquery-ui 1.7.2. All i'm trying to do is use the load
event of the tabs and it doesn't seem to be firing. A simple test
does not alert anything:
$(document).ready(function() {
$('#tabs').tabs({
load: function(event, ui) {
alert('loaded'); //should alert here, never
happens
}
});
Any ideas what the problem might be? Am I doing something wrong?
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