> So...will Imail work OK without the ESMTP commands? You will be deprived of the following functionality, with the associated consequences:
SIZE - Mailers will think they are unable to warn your server upfront about the size of an incoming message, nor will the maximum size of a message be able to be announced from server to client. This will likely have no effect, as the remote server will fall back to just sending the message regardless, letting the server decide whether to reject it after the DATA is sent. 8BITMIME - Mailers will not be requested to send 8-bit MIME encoded messages; some will anyway, while others will switch to alternate encoding. Since Imail continues to support 8-Bit MIME internally whether or not it is announced in the EHLO, there's unlikely to be a problem. DSN - Mailers will assume they cannot request extended DSN options, which could result in non/delivery notifications not being sent at all in some cases. ETRN - Remote dial-up SMTP clients for whom you are queueing mail will be disabled. AUTH - Self-explanatory. EXPN - Users will not be able to list the members of Group Aliases, which is just as well. Be aware in general that turning off ESMTP, which is the default protocol for many mailers, means, as the saying goes, "a persistent small expansion in traffic" for little to no return as the mailers fall back to standard SMTP. As Len said, SMTP Fixup is really half-baked. For instance, the PIX is not gonna save you from, nor detect, a perfectly RFC 821-compliant DoS attack. -Sandy Please visit http://www.ipswitch.com/support/mailing-lists.html to be removed from this list. An Archive of this list is available at: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Please visit the Knowledge Base for answers to frequently asked questions: http://www.ipswitch.com/support/IMail/
