CentOS-4.8 cyrus-imapd-2.2.12-10 sendmail-8.13.1-3.3
I have a mail hub which uses cyrus-imap with sendmail It has worked well for us on this and prior hosts going back to 1995. And, I do not have a problem with the current setup.
What I would like to do however, is to deliver plus-formatted e-mail addresses directly to users subfolders in their mailbox tree. Such addresses take the form userid+subfolder+sub-subfolder@domainname.tld. How this is done I have not discovered. What I always get is an ".Address Unknown" smtp error.
I have gone to both the cyrus and the sendmail lists respecting this issue. While there is a lot of information there following any of it does not seem to lead me anywhere fruitful.
Does anyone here run a sendmail/cyrus-imap combination on CentOS that has direct delivery into user mailbox subfolders using the plus address format working? Is so, would you be so kind as to provide an outline of how this is done?