[jQuery] a tag selector question

Based on http://flowplayer.org/tools/demos/overlay/index.html I tried
to set up an experiment. I wanted to use an anchor tag instead of an
image as the trigger. Note in the following, the second and third
items item work fine but the the first one does not and I can't figure
out why. Any help would be greatly appreciated.

<script>
// What is $(document).ready ? See: http://flowplayer.org/tools/using.html#document_ready
$(document).ready(function() {
$("a[rel]").overlay();
$("a[rel]").css("border","9px solid red");
$("img[rel]").overlay();
});
</script>

--
Michael