ORA-21560 when trying to use the dbms_lob.loadfromfile function

Hello list,
I get this error,  working with the dbms_lob package.
  (NT4, oracle 8.1.7)
  This is the sequence of steps I have followed:
  CREATE OR REPLACE DIRECTORY DIRECT_IMAGEN AS 'E:\DIRECT_IMAGEN';
  CREATE OR REPLACE PROCEDURE insert_image
  AS
  file BFILE;
  lob BLOB;
  BEGIN
  insert into t_image (id, image_lob) VALUES (5, EMPTY_BLOB())
  return image_lob into lob;
  file:=bfilename('DIRECT_IMAGEN','foto1.gif');
  dbms_lob.fileopen(file, dbms_lob.file_readonly);
  dbms_output.put_line(dbms_lob.getlength(lob));
  dbms_lob.loadfromfile(lob, file, dbms_lob.getlength(lob));
  dbms_lob.fileclose(file);
  commit;
  exec insert_image;
  ORA-21560: argument 3 null, not valid or out of range.
  The third argument is the length of the image, which is equal
to 0.
  The directory is in the local machine, as well as the image,
and this machine is the database server. The user has read privileges on this directory,
  What am I doing wrong? A lot of thanks.

begin:vcard
n:Jimenez;Beatriz Martinez
x-mozilla-html:FALSE
org:Fundación CIDAUT;Departamento de Informática adr:;;Parque Tecnológico de Boecillo p.209;Boecillo;Valladolid;47151;Spain version:2.1
email;internet:beamar_at_cidaut.es
title:Ingeniera Informática
fn:Beatriz Martínez Jiménez
end:vcard Received on Fri Jul 27 2001 - 06:11:57 CDT