jQuery Error - xyz is not a function

I am suddenly getting a most unwelcome error on this page:

Error: $("#accordion").accordion is not a function

My jQuery code is as follows:

<script type="text/javascript">
        $(function(){

            // Accordion
            $("#accordion").accordion({ header: "h4", autoHeight: false, collapsible: true });

            //hover states on the static widgets
            $('#dialog_link, ul#icons li').hover(
                function() { $(this).addClass('ui-state-hover'); }, 
                function() { $(this).removeClass('ui-state-hover'); }
            );

            // controls the sidebar navigation action               
            $('.interior #subContent > ul > li > a开发者_运维知识库.drop').click(function(){
            $(this).parent().children('ul').toggle("slow");
                 return false;
            });

            $(window).ready(function() {
                $('li.products ul').show();
                $('li.technical ul').show();
                $('li.tips ul').show();
            }); 

        });
    </script>

I has worked for weeks and today...errors all the way.

I would appreciate any help in determining the cause of the error.

Thanks.

Found the problem:

This:

<script type="text/javascript" src="http://jqueryui.com/latest/ui/ui.accordion.js"></script>

does not link to anything anymore.

The requested URL /svn/tags/latest/ui/ui.accordion.js was not found on this server.