Qmail Mail Server for [url removed, login to view] domain setup in DMZ of a Network, as per setup described in qmailrocks org site, except that there are no mailboxes on this mailserver, only the mail queue. Another similar server is setup within the Local segment of the LAN and this has full setup with mailboxes (vpopmail) etc. [url removed, login to view] has MX of the machine in the DMZ. However, the local LAN is firewalled and the DMZ server cannot initiate connections to relay/deliver mails to the server in the LAN. For this to happen a hole has to be opened in the firewall, even if temporarily.
Instead of doing this we require a patch for qmail, which lets the server in the firewalled LAN open n number of connections, as specified in configuration, to the server in the DMZ and the server in the DMZ to deliver the mails on the same connection. This is currently not possible with Qmail.
Various methods are discussed in archives of the qmailrocks mailing list under the thread "call for patch ideas" in May, 2005. Other resources on the net, including the famous qmail toaster, may also be consulted. Patch is for qmail and not specifically for the QMR installation, though the target is to incorporate into QMR also.
Package serialmail, TURN/ETRN (RFC 821 & RFC 1985) may be an option for patch...see the thread. Any other method is also acceptable, as long as it does not break the way things work nowadays, as serialmail was mostly used when TLS etc. were not there.
Patch will be GPL'd and become part of the qmail open source package.
All communication in PMs please.
With best regards.