Auto complete rjs problem

I want to use auto_complete plugin for a field.

I have a ajax call that loads a js partial that will insert into DOM a
text field with auto complete (the plugin will insert for me css styles,
an input, a div and a new Ajax.Autocompleter call).

The problem is it doesn’t work, it seems the new letter event doesn’t
trigger a new http request for in order to bring the list of matching

Smaller problem: the input has a autocomplete=off attribute to disable
browser default search; this attribute is omitted when the input is
added with an ajax call.

(I succeeded making the auto_complete work when it’s load in the page
from the begining, not later with an ajax call.)