Missing PL/pgSQL library

[PostgreSQL 6.5.1 on i686-pc-linux-gnu, compiled by gcc 2.7.2.3]

Hi,

I installed the PostgreSQL 6.5.1-1 RPM packages that I downloaded from
ftp://postgresql.nextpath.com/pub/postgresql/RPMS/

I then tried to make PL/pgSQL to work by typing in psql, as the postgres
user, in the 'template1' database, these statements from the PostgreSQL
Programmer's Guide, Chapter 43. Procedural Languages

CREATE FUNCTION plpgsql_call_handler () RETURNS OPAQUE AS
'/usr/local/pgsql/lib/plpgsql.so' LANGUAGE 'C';

CREATE TRUSTED PROCEDURAL LANGUAGE 'plpgsql'
HANDLER plpgsql_call_handler
LANCOMPILER 'PL/pgSQL';

It worked with 6.4.2, but with 6.5.1 it complains about
'/usr/local/pgsql/lib/plpgsql.so' being not found. I did a 'find / -name
plpgsql.so' as root and didn't find that file. In fact the directory
'/usr/local/pgsql' doesn't even exists. So I listed the files in the eight
RPMs and found that plpgsql.so is not in any of them. What am I missing? Can
you help me with this?

Thank you for your time

Nicolas Cadou