Choosing PostgreSQL as the database for our next project

Hello everyone!

I've been assigned the task of choosing the database soloution for our
next project and have two questions I need to figure out:

1. Replication - multimaster
I'll try to explain the setup to the best of my ability:
Three centers:
Main center - database with a backup database
Center 1 - database with a backup database
Center 2 - database with a backup database (same as center 1)

Application on the three centers will use the local database but the
data should be replicated to the others as well. So when the link
between the main center and center 1/2 goes down applications will work
as usual and when the link is up the data will be replicated back and
forth so they are equal. I assume that not all of the databases and
tables will be replicated though...
I know that Oracle can do this and they call it multimaster. I read in
the FAQ that presumably pgcluster can do this, but instead of digging
through tons of info I'll ask try my luck here.
Will PostgreSQL be able to do what I want? Any third party (commercial
or not) solutions?

2. Commercial support
<Excerpt from the customer specifications:>
The Database System shall be based (on penalty of rejection) on a
commercial relational database package to ensure simple future
extensions and modifications.
</excerpt>
They're asking the wrong thing her IMO, but that is nothing I can do about.
So, are there any companies that I can point to and say, 'There's your
commecial vendor'?

regards
--
Johnny Ljunggren, Vestlia 6, 3080  HOLMESTRAND, 918 50 411