Planet Ergo

What is referred to as 'condstore' is actually the feature-set that IMAP4Rev1 extension added in RFC 4551. It enables the quick synchronization of flags on messages as well as other conditional STORE operations.

I'm going to have to refer you to the RFC for the full details, but suffice it to say your Kolab 2.3 deployment could greatly benefit from enabling said extension on your mailboxes - it is not enabled by default as part of Cyrus IMAP 2.3, only with Cyrus IMAP 2.4 is the 'condstore' annotation set to 'true' by default.

You will have to execute two separate actions on your Kolab server:

1. Configure new mailboxes to have 'condstore' enabled by default,
2. Configure current mailboxes with 'condstore' enabled.

You would preferrably execute these actions in this order, to reduce the chance new mailboxes are being created while you have not yet switched on 'condstore' to be enabled by default.

Enable 'condstore' by default

To enable condstore by default, in your favorite editor, add the following line to /kolab/etc/kolab/templates/imapd.conf.template:

mailbox_default_options: 2

Afterwards, write out new templates and reload Kolab with the new configuration;

/kolab/sbin/kolabconf

Enabling 'condstore' on existing mailboxes

To enable 'condstore' on existing mailboxes, login to Cyrus IMAP using the cyradm utility:

cyradm -t "" -u manager localhost

From there, you can examine one of the existing mailboxes;

localhost> info user/john.doe@example.org
{user/john.doe@example.org}:
  condstore: false
  duplicatedeliver: false
  lastpop:  
  lastupdate: 12-Sep-2011 17:56:54 +0200
  partition: default
  pop3newuidl: true
  sharedseen: false
  size: 105382261
  folder-test: true

As you can see in the example, condstore has not yet been enabled for this mailbox. To enable condstore for a particular mailbox:

localhost> mboxcfg user/john.doe@example.org condstore true

You will not want to repeat this command for all mailboxes, but instead use wildcard matching:

localhost> mboxcfg user/*@example.org condstore true

NOTE: The two commands do not return any output.

NOTE^2: Don't forget to, at your option, also enable condstore for mailboxes in the shared namespace, in other authentication realms, and perhaps even for those mailboxes that reside in the DELETED namespace (just in case they are restored to a visible namespace later on in life).