Just to add to the list (although I'm sure people through trial and error would figure it out) here's what I had to run to sync my courier-imap server with Zimbra:
Originally Posted by sickdm
First on my courier IMAP server I needed to edit the imapd file.
I had to add an AUTH method as it wasn't there:
# vi imapd
Then the sync command I used:
IMAP_CAPABILITY="IMAP4rev1 AUTH=CRAM-MD5 \
AUTH=CRAM-SHA1 CHILDREN NAMESPACE \
THREAD=ORDEREDSUBJECT THREAD=REFERENCES \
SORT QUOTA IDLE"
./imapsync --nosyncacls --syncinternaldates \
--host1 old_host --user1 old_user --password1 'my_pass_1' \
--host2 zimba_host --user2 new_user --password2 'my_pass2' \
--ssl2 --authmech2 PLAIN