JQuery AutoComplete (UI 1.8rc3) With Web Service

I have this version of the autocomplete control working when returning XML from a .ashx handler. The xml looks like this:

<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
<States>
<State>
<Code>CA</Code>
<Name>California</Name>
</State>
<State>
<Code>NC</Code>
<Name>North Carolina</Name>
</State>
<State>
<Code>SC</Code>
<Name>South Carolina</Name>
</State>

The autocomplete code looks like this:

$('.autocompleteTest').autocomplete(
{
source: function(request, response) {
var list = [];
$.ajax({
url: [URL]
dataType: "xml",
async: false,
data: request,
success: function(xmlResponse) {
list = $("State", xmlResponse).map(function() {
return {
value: $("Code", this).text(),
label: $("Name", this).text()
};
}).get();
}
});
response(list);
},
focus: function(event, ui) {
$('.autocompleteTest').val(ui.item.label);
return false;
},
select: function(event, ui) {
$('.autocompleteTest').val(ui.item.label);
$('.autocompleteValue').val(ui.item.value);
return false;
}
});

For various reasons, I'd rather be calling an ASP.NET web service, but I can't get it to work. To change over to the service (I'm doing a local service to keep it simple), the start of the autocomplete code is:

$('.autocompleteTest').autocomplete(
{
source: function(request, response) {
var list = [];
$.ajax({
url: "/Services/GeneralLookup.asmx/StateList",
dataType: "xml",

This code is on a page at the root of the site and the GeneralLookup.asmx is in a subfolder named Services. But a breakpoint in the web service never gets hit, and no autocomplete list is generated. In case it makes a difference, the XML that comes from the asmx is:

<?xml version="1.0" encoding="utf-8" ?>
<string xmlns=[URL]><State> <Code>CA</Code> <Name>California</Name> </State> <State> <Code>NC</Code> <Name>North Carolina</Name> </State> <State> <Code>SC</Code> <Name>South Carolina</Name> </State></string>

Functionally equivalent since I never use the name of the root node in the mapping code. I haven't seen anything in the jQuery docs about calling a .asmx service from this control, but a .ajax call is a .ajax call, right? I've tried various different paths to the .asmx (~/Services/), and I've even moved the service to be in the same path to eliminate these issues. No luck with either.