Voting form input/select id doesn't match the label's "for" field

Hi

I'm finding that my fivestar voting form input has a different id than the matching label's "for" field. Here's the code for the label:

<label for="edit-vote">Your rating: </label>
and the matching input/select field...
<select name="vote" class="form-select" id="edit-vote-0" >....
For some reason Drupal has suffixed the form id with -0, even though this is the only voting widget on the page.

Does anyone know how this can be fixed?

Thanks
Dan