Placing Filters in Fieldsets Breaks Ajax functionallity

Ok, here is what i got:

I put up a custom version of a views-view--page.tpl.php to place all filters in a collapsible fieldset.
I somehow hackt it in the file the ugly way - but there should not be any mistakes - except that i should have used a preprocessing function, shouldn't I?

The only thing i changed is the following:

  <?php if ($exposed): ?>
    <div class="view-filters">
      <?php $title = 'Filter';
      $fieldset = array('#title' => $title,'#collapsible' => TRUE,'#collapsed' => TRUE,'#value' => $exposed);
      print theme('fieldset', $fieldset);
      ?>
    </div>     
  <?php endif; ?>

The display is working, except that the Filter produces scrollbars to appear in the div.fieldset-wrapper - don't know why.
The other thing is, that updating the filter via ajax request produces a timeout.

The View itself works in the editing screen, so there must be some problem with the fieldset i guess.

You can try it yourself at http://synced-guild.net/rooster

I'll keep on trying to fix it, but I also wanted to post it here.

Bye