Postgres planner bug in 7.3.x and 7.4.1 ?

Hello

We're experiencing weird behaviours with both Postgres 7.3.x and 7.4.1
versions, relating to views based on views including fields based upon
plpgsql functions. Attached is a .sql file showing our problems, from a
co-worker who doesn't have immediate access to this mailing list.

Here's the psql output on a 7.4.1 version (t1, t2 already created), showing
the function being called :

postgres(at)msi:/$ psql -p5433 -d t2g_3 -f /tmp/t1.sql
You are now connected as new user postgres.
psql:/tmp/t1.sql:32: ERROR: function "plpgsql_call_handler" already exists
with same argument types
psql:/tmp/t1.sql:35: ERROR: language "plpgsql" already exists
CREATE FUNCTION
CREATE VIEW
CREATE VIEW
CREATE VIEW
CREATE VIEW
psql:/tmp/t1.sql:284: NOTICE: f1 >>>>>>>> 8980
psql:/tmp/t1.sql:284: NOTICE: f1 >>>>>>>> 8981
psql:/tmp/t1.sql:284: NOTICE: f1 >>>>>>>> 8982
num_adr | num_person | firstname | name
---------+------------+-----------+------
6231 | 8982 | Chico | Marx
(1 row)

num_adr | num_person | firstname | name
---------+------------+-----------+------
6231 | 8982 | Chico | Marx
(1 row)

Thanks for any support

laurent