Forum OpenACS Q&A: Response to Postgres, distributed databases, two phase commits, or other replication strategies....


I think you're requirement is typically met by the use of an App Server.  two-phase commit is one of the ways they justify charging $10-40K per CPU.

Have you looked at clustering or synchronizing a distributed caching tier instead of the database?  I'd think that's  much simpler over a WAN.

Also,  you might have more luck poking around  Again,  the app server folks seem to be solving these problems all day long.