Autocompleter - get rid of default selection?

Running Scriptaculous 1.8.1 I'm experiencing an issue with the autocompleter.

As part of a search page, I've added and autocomplete field. During entering text, the first entry in the autocomplete list is automatically selected- once the user hits enter (regardless if that is the entry he's looking for or not), the form is submitted.

I'm looking for a way to not have any autocompletion entry selected by default- instead I want the user be able to do that by using "cursor down" initially to actually step into the dropdown list.

Thought that the "autoselect" property of the Autocompleter did control that but apparently doesn't.

Any ideas?

Thanks, Andi