Created Unassigned: Adding new item. Blank fields. [10258]

Ok, this looks like it should be easy, so what am I missing?
This is my little test method. The result is a item with no Title. I would expect an item with Test in the Title field.

```
$().SPServices({
operation:"UpdateListItems",
async: false,
listName:"TestList",
batchCmd:"New",
valuePairs:[["Title","Test"]],
completefunc:function(xData,Status){
alert("Done");
}
});
```

Thanks