Rails spinoffs - Sep 2005 - What did I forget

Hi-
I am trying to use the ajax autocompleter.
In my page there is

<input type="text" name="tt" value=""
id="tt"/>
<div id="myid"/>
  

and later on

new Ajax.Autocompleter(''tt'',
''myid'',''http://localhost:8080/port/app?action=manufacturers&qp=tt&service=txtile&tt=42'',
{ } );
  

The server recieves an AJAX request, and returns

    <?xml version="1.0" encoding="UTF-8"?>
    <ul>
    <li>[Ljava.lang.Object;@3cb948</li>
    </ul>

But the drop down does not apear on the page.

What did I forget?
Cheers,
Ron