On May 19, 2009, at 1:05 AM, Max Ivanov wrote:

I'm current maintainer of dovecot packages in ALTLinux distro and I plan to make possible to install multiple dovecot versions side-by-side (1.0, 1.1, 1.2) to make upgrade process easier and more robust.

So you mean actually running both at the same time? The most important
part is to have different base_dir for each Dovecot installation.

Is there any consequences of doing that? I worry about locking maildirs and mboxes, does dovecot handle it correctly if another dovecot process tries to work on same mail location?

Yes. Works just fine. I even ran stress testing v1.0 and v1.1 at the
same time modifying the same mailbox. Although that was around v1.1.0
release, hopefully it hasn't broken since. :)

There is one minor incompatibility with v1.0 and v1.1 index files, but
it has to do with handling \recent flags and shouldn't really cause
any real problems. They were more or less broken in v1.0 (and most
other IMAP servers) anyway.