How to override "action" of a form?
The $form_id argument is the internal form ID, not the CSS ID. For views exposed forms it'll always be views_exposed_form.

I think this is the easiest way to target a specific exposed form:

function MYMODULE_form_views_exposed_form_alter(&amp;$form, &amp;$form_state, $form_id) {
  $view = $form_state['view'];
  if ($view-&gt;name == 'foo' &amp;&amp; $view-&gt;current_display == 'bar') {
    // Alter the form...
  }
}