> I want to upgrade a system from 7.3.8 ro 8.1.5
> I am new to Psql and looking for handy hints
> Any known problems or pit-falls ?
> Anything we need to do in preparation ?
The Postgresql manual is a good place to start:
http://www.postgresql.org/docs/8.1/interactive/install-upgrading.html
http://www.postgresql.org/docs/8.1/interactive/migration.html
This will give you all the guidelines to follow to safely upgrade your server.
Regards,
Richard Broersma Jr.