Dovecot replication - notify not working

Dear Dovecot-Admins,

I've set up a pair of Dovecot Servers, please find config of server one attached. They are configured to replicate changes over a tcp connection using port 12345, set up as described in http://wiki2.dovecot.org/Replication article page.

Adding the user postboxes to replication using "doveadm replicator add '*' " syncs the mailboxes as expected. Unfortunately both of the servers does not propagate any changes, e.G. new mail in Sent folder. Removing and adding the mailboxes again syncs them again.

Can anybody help me to get the notify working, please?

many thanks in advance, Jonas