Cyrus IMAP and MySQL mailboxes (Building load-balancing cluster)

[Igor Zhbanov]

So, what is the best way to build load-balancing Cyrus IMAP cluster?
Nginx, perdition, Cyrus IMAP Aggregator, Cyrus IMAP murder, Cyrus IMAP
replication?

And can you tell me what problems to high-availability can happen when
using Cyrus IMAP replication? In what situations it is unreliable? And
is it possible to avoid it?

Thanks to all!