I have noticed that Zimbra's spam training and recognition is not improving over time as I expected it would. I've concluded that I don't really understand how Zimbra performs training as well as I should.

Three related questions:

1. I know that users can help Zimbra spam training by manually using the Junk / Not Junk button on the toolbar. However, does dragging a message into the Junk folder trigger similar learning behavior? This is important for us, as most of our users interact with Zimbra via something other than the web interface (mostly Thunderbird, sprinkling of other IMAP clients). It would be nice if they could drag mail to the Junk folder and have it learned.

2. Does marking a message as Junk using Thunderbird's Junk / Not Junk button (or similar buttons in other clients) do anything useful for Zimbra training?

3. This command is in zimbra's crontab: /opt/zimbra/bin/zmtrainsa
What is the behavior of this? From running it manually, I see it is looking only at the user zimbra's folder(s), but I can't tell which folder(s) or what it is doing. Is there any mechanism by which EVERY user's Junk folder is analyzed on a regular basis?

Ultimately, what I think we want is for users to be able to help Zimbra train by dragging messages to their Junk folder. In the meantime, I am manually running zmtrainsa on my own Junk folder once a week to help the process.

Any thoughts or advice here will be much appreciated. Thanks!