TIdIdentErrorType is used to specify the error to send to the Ident client in the ReplyError method.
ieInvalidPort - The port specified by the query is not valid
ieNoUser - The port pair specified is not in use or not used by an identifiable entity
ieHiddenUser - The user was identified but wishes to remain anonymous
ieUnknownError - The server indicated another problem, could not identify the problem, or in place of the other codes if for example, the server wishes to hide something that is implied by the other errors