Mixing library versions

I'm currently experimenting with the Debian packaging of 6.4.

The question arises of how to handle the change in library versions from
1.0 to 2.0. It has been suggested that I should keep libpq.so.1 around
for the benefit of those who need to communicate with an older database
server.

Is it possible to use libpq.so.2.0 to query a remote database whose
server is running PostgreSQL 6.3? What would be the consequences of
using libpq.so.1 to query a 6.4 server?

--
Oliver Elphick Oliver(dot)Elphick(at)lfix(dot)co(dot)uk
Isle of Wight http://www.lfix.co.uk/oliver
PGP key from public servers; key ID 32B8FAA1
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