database session variables

Hi all,

I am working on a system architecture that requires accessing session variables specific to the database connection. This is useful because you can emulate many users (with different privileges) with a single database logon. Currently it seems like only user, current_user and session_user are supported.

What I would like is the ability to define and set my own session variables (the same way you can use package variables in oracle). Failing that, I need some way to uniquely identify the database session (e.g. a session_id function similar to session_user).

I would really like to use PostgreSQL but won't be able to if there is no way of accessing the session 'id'.

Is this currently possible, or are there any plans to add such to PostgreSQL in the future?

Cheers,
Mark