check x and y to handle leave event properly drag and drop html5

gistfile1.js

    $('#draganddrop-wrapper').hide();

    $(document).bind('dragenter', function(event) {
        $('#draganddrop-wrapper').fadeIn(500);
        return false;
    });

    $("#draganddrop-wrapper").bind('dragover', function(event) {
        return false;
    }).bind('dragleave', function(event) {
        if( window.event.pageX == 0 || window.event.pageY == 0 ) {
            $(this).fadeOut(500);
            return false;
        }
    }).bind('drop', function(event) {
        handleDrop(event);

        $(this).fadeOut(500);
        return false;
    });