public void deleteFolder(long folderId) throws PortalException, SystemException {

    if ((account.getDraftFolderId() == folderId)
        || (account.getInboxFolderId() == folderId)
        || (account.getSentFolderId() == folderId)
        || (account.getTrashFolderId() == folderId)) {

      throw new MailException(MailException.FOLDER_REQUIRED);
    }

    _imapAccessor.deleteFolder(folderId);

    FolderLocalServiceUtil.deleteFolder(folderId);
  }