I recently upgraded Plesk 11.5 to 12.0 (on CentOS 6.5) and would like to switch the email server from Courier to Dovecot. I know how to do that, physically, in the Plesk panel, but what I don't know is what happens to existing emails. Does Plesk migrate them automatically, or is there some way for me to do it with commands? I'm hoping the answer is not to tell each user they have to save and restore messages on their own. I've searched this forum (and elsewhere) for this topic but didn't find anything. Thanks.