form_values missing a value?

All,

I can't seem to put my finger on this. I have a simple form with three fields. It works perfectly, until I create a theme() function for it. Here's the form code:

    $form['term'] = array (
      '#type' => 'textfield','#title' => 'Query String',
      '#required' => TRUE,'#default_value' => $term,
      '#autocomplete_path' => 'staff/autocomplete',
      '#size' => 32,'#maxlength' => 128);
    $form['type'] = array(
      '#type' => 'select','#title' => 'Type','#default_value' => $type,
      '#options' => array ('callhistory' => t('History'),'authlog' => t('Authentication')));
    $form['when'] = array(
      '#type' => 'select','#title' => 'When','#default_value' => $when,
      '#options' => array (
          'today' => t('Today'),'yesterday' => t('Yesterday'),
          'week' => t('This Week'),'lastweek' => t('Last Week'),
          'month' => t('This Month'),'lastmonth' => t('Last Month')));
    $form['submit'] = array('#type' => 'submit','#title' => 'blah','#value' => t('Go'));

Here's the theme code:

function XXtheme_staff ($form) {
  $output = '<table border="0" cellpadding="0" cellspacing="0"><tr><td>';
  $output .= form_render($form['term']);
  $output .= '</td><td>';
  $output .= form_render($form['type']);
  $output .= '</td><td>';
  $output .= form_render($form['when']);
  $output .= '</td><td>';
  $output .= form_render($form['submit']);
  $output .= '</td></tr></table>';
  return $output;
}

Any suggestions on what I can do without going directly to $_POST[edit][term]? (yup, it's there).

Thanks,