Found the issue, I uploaded a fixed dovecot into the dapper-security queue. It's currently blocked by the mirroring problems, but that should be resolved soon. Thanks for the report and sorry for screwing up.
** Changed in: dovecot (Ubuntu) Status: In Progress => Fix Committed -- dovecot security update (5.1) breaks mysql https://launchpad.net/bugs/49601 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs