TABLE FUNCTION, ERROR: WRONG RECORD TYPE IN RETURN NEXT

Hi,
I having some problem with table function that returns set of 'type',

Error says: Wrong record type supplied in return next, why it so?
Thanks.


type:
public.my_type ( name varchar(800), ncount int4, total int4 )

function:
CREATE FUNCTION public.doit() RETURNS SETOF public.my_type AS '
DECLARE
    rec       RECORD;
BEGIN
    FOR rec IN
        SELECT public.getname( fullname ) AS fullname,
            COUNT( userid ) AS ncount,
            ROUND(10000.0 * CAST( COUNT( userid ) AS bigint
) / 10000, 0) AS total
                ....
    LOOP
        RETURN NEXT rec;
    END LOOP;
    RETURN;
END;