>>>>> "Johnny" == Johnny Billquist <bqt@Update.UU.SE> writes:

    >>> Since noone have mentioned /etc/hosts.deny yet, I'll do it.
    >>> Simple, you can do it based on hostnames or ip-address ranges,
    >>> and while I think you do get through the connect stage, the
    >>> port is immediately disconnected again.

    >> Hm -> this is a nice way, anyway it only works from inetd.

    Johnny> No, I believe it works for all applications, including
    Johnny> sendmail/postfix.

... for all applications that are compiled/linked against libwrap
(check with ldd). This seems to be valid for sendmail, but not for
postfix.

Markus.