Taxonomy doesn't autocomplete after the module is activated

I installed the module, and since it got activated, the taxonomy autocomplete field has not been working anymore.
If I create a new node of a content type that has a tag taxonomy associated, I am not able to get the terms I insert autocompleted (and I know I am typing a term that is present in the taxonomy, as I see it listed in the taxonomy terms list).
When I disable the module, the autocomplete fields works again.