Seems to work.
There's a cavecat, if zarafa was installed before with another plugin as the unix-plugin and the data is restored from a backup. While smeserver-zarafa enables zarafa for all users in default, it has to be disabled globally - if i.e. the db-plugin was used before. After re-enabling zarafa for each user, it works as expected. In my installation the user maillog gets a copy of all emails. If you don't follow the way I described, maillog won't receive any copy.
In addition z-push is also working installing the latest rpms.
I'll add this to the wiki - if you want me to.
Thank for your work.
stefan