QUOTE(Wazoo @ Sep 26 2007, 07:02 PM)

IMAP is a connection between the user's machine and the hosting ISP ... this would not be SpamCop's servers talking to other servers.
This far, Trevor's descriptions have been about IMAP software on various SpamCop servers. On the other hand, this IMAP software would be dealing with the same data/databases .. and based on the description of some login issues sometime earlier today that apprently impacted 'everything' ....????
Wazoo, If I were to hazard a guess, I would say that SpamCop is using POP3 to pull messages from various ISP as well as receiving some messages as being directly forwarded from ISP or sent directly to the SpamCop account.
There would appear to be a series of servers involved that may be processing the mail using IMAP to move it from one server to the next.
Mail comes in and has to process through an initial set of filters which then sends some mail to the held mail folder and other mail to the inbox and maybe some mail elsewhere???.
The VER interface accesses the held mail folder and assigns it own set of record numbers to that mail
The WebMail interface accesses all the mail in multiple folders and assigns mail in each folder with its own record number that changes as mail is added and or removed from each folder.
The WebMail interface also has its own set of filters that sorts and handles the mail.
The VER interface moves mail from the heldmail database to one or two separate directions.
1) It can simply send the mail to the trash folder (database)
2) It can send the mail to the quick reporting database and delete it from the user's mail box
3) It can send the mail to be queued for full reporting and delete it from the user's mail box
4) It can send the mail to be queued for full reporting but leave a flagged copy in the held mail database
5) It can move the mail from held mail to the inbox or forward it somewhere else dependant upon the user's preferences.
6) It can move the mail from held mail to the inbox or forward it somewhere else dependant upon the user's preferences and also white list the mail making yet another entry is some database
The WebMail interface provides for some of the same; moving messages from place to place and doing some form of Quick Reporting that also deletes the message. Full reporting is not a feature of WebMail, but it can be used to forward mail to a reporting account just as you would from any non SpamCop mail client.
The point is that there is a lot of precessing going on in the background connecting servers on opposite ends of the country each doing their own thing with the mail and apparently some of that is being done using some type of IMAP interface or code or protocol.
Now keep in mind that there are multiple servers (blades) doing load balancing that are not all configured the same (as seen with the various versions of SpamAssassin being used) and the recently added grey listing function added to the multiple sets of filters than can be used, there are countless possibilities for odd behaviour.
No how's that for sticking my foot in my mouth?