I need to replicate some new databases.

We have 5 shards, each with an identical schema. Each of these will be
replicated to a slave (5 masters, 5 slaves).

Do I need 5 separate clusters, or can I do this with a single cluster
and 5 replication sets? I'll be using PG 8.4 and Slony-I 2.0.7.

I suspect I need 5 separate clusters, and I'm less likely to blow my
foot off with this setup, but I'm soliciting opinions before I proceed
:-)

-- 
Stuart Bishop <stuart at stuartbishop.net>
http://www.stuartbishop.net/