Error message due to taxonomy terms with special characters

I just installed the 1/18 dev release and I'm getting the following error on import of messages:

warning: preg_replace() [function.preg-replace]: Unknown modifier 'E' in /home/dcogco5/public_html/drupal/sites/all/modules/mailhandler/plugins/mailhandler/commands/MailhandlerCommandsDefault.class.php on line 27.

The relevant code appears to be:

    $commands = $this->getCommands($message['body_text']);
    $this->commands = $commands;
    foreach ($commands as $key => $value) {
      $message['body_html'] = preg_replace('/' . $key . ': ' . $value . '/', '', $message['body_html'], 1);
      $message['body_html'] = preg_replace('/<br[^>\r\n]*>/', '', $message['body_html'], 1);
    }

But there is no apparent modifier 'E' in the code.