Search Module Invalid argument supplied in common.inc on line 703

I get the following error whenever a search is performed on my site. It is displayed at the top of the page before anything else, but the results of the search are displayed where they should be. THis doesn't seem to make sense to me, but oh well - it is almost 3am so not much makes sense right now anyway.

Anyone else seen this or have a fix? I couldn't find anything like this in the forums already.

warning: Invalid argument supplied for foreach() in /hsphere/local/home/keithmcd/bleak1.keithmcd.com/includes/common.inc on line 703.

/**
 * Perform a global search on the given keys, and return the formatted results.
 */
function search_data($keys = NULL) {
  $edit = $_POST['edit'];
  $output = '';

  if (isset($keys)) {
    foreach (module_list() as $name) {
      if (module_hook($name, 'search') && (!$edit['type'] || $edit['type'][$name])) {
        list($title, $results) = module_invoke($name, 'search', $keys);
        if ($results) {
          $output .= '<h2>'. $title .'</h2>';
          $output .= '<dl class="search-results">';
          foreach ($results as $entry) {            <-- This is line 703
            $output .= search_item($entry, $name);
          }
          $output .= '</dl>';
        }
      }
    }
  }