obtaining results from trigger

Hello everyone, I was hoping someone could help me with this...

I'm running postgres 7.02 on redhat 6.2, apache 1.3.14 and mod_perl
1.24_01. I'm also using perl modules DBI 1.14 and DBD-Pg-0.95 to acces
the Postgres database.

Everytime my inventory file gets updated, I would like to have the
quantity on hand returned to my perl script. I set up the following
function to do this:

CREATE FUNCTION inv_lookup () RETURNS OPAQUE AS '
BEGIN
RAISE NOTICE ''%'', NEW.qtyonhand;
RETURN new;
end;
'language 'plpgsql';

Then I create the trigger like this...

CREATE TRIGGER qty after inventory for each row execute procedure
inv_lookup();

If I do any sort of updates from within psql I get the correct data
which is the Qtyonhand field in this format:

NOTICE: 15

However, in my perl program, I'm unsure as to how to get this
information back. The Postgres Documentation says that the results from
a Notice get sent back to the application, but I check the DBI->err,
DBI->errstr, and DBI->state and they are empty. The result code for the
actual SQL command I run is just 1 for success.

Does anyone know how to get these results from within a perl scripts???
Thanks in advance for any help.

Chris.