Pgsqlv7.3RC1, pgadminII v 1.4.0 Dropping a field does not drop asociate foreign key

I have the next table:

CREATE TABLE aenor_subexpediente (
  id_aenor_subexpediente int4 DEFAULT
nextval('"aenor_subexpe_id_aenor_sube_seq"'::text) NOT NULL,=20
  subexpediente varchar(30),=20
  id_tecnico int4,=20
  id_delegacion int4,=20
  id_contacto int4,=20
  id_cnae int4,=20
  alcance_certificacion varchar(100),=20
  id_t_aenor_subexpediente int4,=20
  id_area int4,=20
  CONSTRAINT aenor_subexpediente_pkey PRIMARY KEY
(id_aenor_subexpediente),=20
  CONSTRAINT id_area_fk FOREIGN KEY (id_area) REFERENCES tm_area
(id_area) ON DELETE SET NULL ON UPDATE CASCADE NOT DEFERRABLE INITIALLY
IMMEDIATE,=20
  CONSTRAINT id_cnae_fk FOREIGN KEY (id_cnae) REFERENCES cnae (id_cnae)
ON DELETE SET NULL ON UPDATE CASCADE NOT DEFERRABLE INITIALLY IMMEDIATE,

  CONSTRAINT id_contacto_fk FOREIGN KEY (id_contacto) REFERENCES
contactos (id_contacto) ON DELETE SET NULL ON UPDATE CASCADE NOT
DEFERRABLE INITIALLY IMMEDIATE,=20
  CONSTRAINT id_delegacion_fk FOREIGN KEY (id_delegacion) REFERENCES
tm_delegaciones (id_delegacion) ON DELETE SET NULL ON UPDATE CASCADE NOT
DEFERRABLE INITIALLY IMMEDIATE,=20
  CONSTRAINT id_t_aenor_subexpediente_fk FOREIGN KEY
(id_t_aenor_subexpediente) REFERENCES t_aenor_subexpediente
(id_t_aenor_subexpediente) ON DELETE SET NULL ON UPDATE CASCADE NOT
DEFERRABLE INITIALLY IMMEDIATE,=20
  CONSTRAINT id_tecnico_fk FOREIGN KEY (id_tecnico) REFERENCES
tm_tecnicos (id_tecnico) ON DELETE SET NULL ON UPDATE CASCADE NOT
DEFERRABLE INITIALLY IMMEDIATE
) WITH OIDS;

I have dropped a field with pgadmin 1.4.0 but the FK is not DROPPED and=20
If i try insert a record in this table i get hext error: constraint
id_tecnico_fk: table aenor_subexpediente does not have  an attribute
id_tecnico
when i try dropping the fk i get the error that it does not exist,=20=20

Rafa