Chari,
> 1. All earlier versions of PostgreSQL are able to be editted via an ssh
> Shell or some other Unix-based platform.
within the postgresql directory there is a /bin directory. There you
will find psql.exe, which will allow you that shell access.
Within PG_ADMIN there is also a SQL-Button in the Symbolarea, after
selecting a database and clicking on it you can still do create table
...
> 2. Is there a way to replicate databases across different servers?
http://gborg.postgresql.org/genpage?replication_research
> 3. Is there a way to cluster servers?
I don't have information about this.
Harald