Error installing instrumentation functins on FreeBSD 6.1

I am having some minor issues installing the instrumentation functions
on FreeBSD.
I copied th admin81 directory into the contrib folder and modified the
Makefile to also read that directory.
So far so good. I do see admin81.so in /usr/local/pgsql/lib

I restarted postgres.

I conncted from a remote windows pgAdmin3.
Connected to template1 (which is where I see the specific functions in
pg_catalog on my windows server).

Loaded admin81.sql. Execute it. I am getting the following error:

ERROR: could not access file "$libdir/admin81": No such file or
directory

Any assistance will be appreciated.

Regards,

Benjamin