Setting session global variables

Is there a way to set a session global variable in PostgreSQL? The only
thing I see are examples of setting config variables. What I would like
to do is this:

Have a table "insertedby" or something that has

created_object oid,
created_by_user oid,
creation_date datetime

Then have a procedure, so that any table that wanted to record who
inserted which record could just use that procedure as an insert
trigger. The trigger would simply read the "current_user" session
variable (which the client had presumably set upon connection) and use it
to populate the "created_by_user" field.

However, the only way I can see to implement this is to have session
global variables. Is there a way to fake session global variables with a
table? Any comments would be appreciated.

Jon

johnnyb6(at)sdf(dot)lonestar(dot)org
SDF Public Access UNIX System - http://sdf.lonestar.org