[Dovecot] moving from BSD to Ubuntu

hi..

im planning to move my Mailserver from an FreeBSD Box to an Ubuntu 12.04 LTS Box. Both Boxes run Dovecot 2.0

Does anyone did this before and experienced any problems ? Downtime is no problem, my plan is to stop Dovecot on the Bsd Box and copy all Mailbox files to the Uuntu system and start dovecot.

Regards Hans