Can't use absolute path for Report Repository

My normal file storage is outside of the Drupal code directory, in "/var/www/drupal-files". However, Forena insists upon changing this to "var/www/drupal-files" which obviously won't work.

The bug seems to be here:

function forena_report_path() {
  $report_path = variable_get('forena_report_repos', '');
  if (!$report_path) {
    $report_path = variable_get('file_' . file_default_scheme() . '_path', conf_path() . '/files/reports');
  }
  return trim($report_path, '/');
}

That "trim" really should be "rtrim".