We migrated from Exchange to Zimbra in December. We were using 4.5.10 if I recall correctly. The additional folders (besides inbox) would periodically poll in the mail client and show the number of unread messages.

Since we upgraded to the 5.0.x GA releases (Network Edition... now running 5.0.6 GA), the folders don't poll automatically and consistently. They frequently show the wrong count if they show a count at all and clicking on the folder does re-read the listing and correct the number of unread messages, but only after the manual selection of the folder.

Anyone else seeing this behavior and is there something I can do to fix it? Or should this be submitted as a bug?

I am using Mail.app, others are running Thunderbird, Entourage, iPhone and Palm Treo's via IMAP. The behavior is consistent across the board.