Prevent an element from “capturing” the mouse using jQuery?

<div style="text-align:center; padding-top:50px;">
    <div id="doc" style="width:384px;height:512px;">
    <iframe id="docFrame" style="width: 100%; height: 100%;"
 src='http://www.ready.gov/america/_downloads/sampleplan.pdf'>
    </iframe></div></div>
    <div id="data"></div>
    <script type="text/javascript">
        $(document).ready(function() {
        var obj = $('#docFrame');
            $('#doc').resizable({handles:'all', resize: function(e, ui) {
                $('#data').html(ui.size.width + 'x' + ui.size.height);
                obj.attr({width: ui.size.width, height: ui.size.height});
            }});
        });
    </script>

$(document).ready(function() {
    var obj = $('#docFrame');
    $('#doc').resizable(
    {
        handles: 'all',
        resize: function(e, ui) {
            $('#data').html(ui.size.width + 'x' + ui.size.height);
            obj.attr({ width: ui.size.width, height: ui.size.height });
        },
        start: function(e, ui) { $('#docFrame').hide(); },
        stop: function(e, ui) { $('#docFrame').show(); }
    });
});

<div style="text-align: center; padding-top: 50px;">
    <div id="doc" style="width: 384px; height: 512px; position: relative;">
        <div id="overlay" style="position: absolute; top: -5px; left: -5px;
            padding: 5px; width: 100%; height: 100%; background: red;
            opacity: 0.5; z-index: 1; display: none;"></div>
        <iframe id="docFrame" style="width: 100%; height: 100%; position: relative; z-index: 0;"
            src='http://www.ready.gov/america/_downloads/sampleplan.pdf'></iframe>
    </div>
</div>
<div id="data"></div>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.2.6/jquery.js" type="text/javascript" charset="utf-8"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.5.3/jquery-ui.js" type="text/javascript" charset="utf-8"></script>
<script type="text/javascript">
    $(document).ready(function() {
        var obj = $('#docFrame'), overlay = $('#overlay');
        $('#doc').resizable({
            handles: 'all',
            start: function() {
                overlay.show();
            },
            resize: function(e, ui) {
                $('#data').html(ui.size.width + 'x' + ui.size.height);
                obj.attr({
                    width: ui.size.width,
                    height: ui.size.height
                });
            },
            stop: function(e, ui) {
                overlay.hide();
            }
        });
    });
</script>