I'm lost :-( with FOR...IN

Hi,

I' still with my stored procedure :

-- Function: SP_U_001(typeofarticle varchar)

-- DROP FUNCTION SP_U_001(typeofarticle varchar);

CREATE OR REPLACE FUNCTION SP_U_001(IN typeofarticles VARCHAR)
  RETURNS SETOF active_articles AS
$BODY$
DECLARE
    myrec RECORD;
    res active_articles;
/**************************************/
BEGIN
  FOR myrec IN
    select *
    from articles, articletypes, department
    where
        articletypes.articletype_type = $1
    AND articles.articletype_id = articletypes.articletype_id
    AND articles.department_id = department.department_id
    AND articles.validity_period_end > now()
  LOOP
    IF (myrec IS NOT NULL) THEN
        res.article_type := myrec.articletypes.articletype_type;
        res.article_author := myrec.articles.author;
        res.department_owner := myrec.department.department_name ;
        res.department_picture := myrec.department.department_picture;
        res.article_title := myrec.articles.title;
        res.article_content := myrec.articles.content;
        res.date_creation := myrec.articles.creation_date ;
        res.date_start := myrec.articles.validity_period_start;
        res.date_end := myrec.articles.validity_period_end;
    END IF;
      RETURN NEXT res;
    END LOOP;
    RETURN;
END;
$BODY$
  LANGUAGE 'plpgsql' VOLATILE;
ALTER FUNCTION SP_U_001(VARCHAR) OWNER TO immensesk;
GRANT EXECUTE ON FUNCTION SP_U_001(VARCHAR) TO immensesk;

whatever, i do the argument VARCHAR will be stored in double quote as "varchar" when i check via pgAdmin GUI. Even if in command line it looks like above.

I still have the same error message on "myrec" :
ERROR:  schema "myrec" does not exist
CONTEXT:  SQL statement "SELECT  myrec.articletypes.articletype_type"

i do not understand as there is quite the same example in postgreSQl 8.1.4 documentation on page 623-624 about "Looping Through Query Results".
so where am i wrong ?

Al.