BUG #3973: pg_dump using inherited tables do not always restore

The following bug has been logged online:

Bug reference:      3973
Logged by:          Alex Hunsaker
Email address:      badalex@gmail.com
PostgreSQL version: 8.3.0
Operating system:   Linux
Description:        pg_dump using inherited tables do not always restore
Details:

create table junk (val integer not null, val2 integer);
create table junk_child () inherits (junk_1);
alter table junk_child alter column val drop not null;
insert into junk_child (val2) values (1);

pg_dump -t junk -t junk_child

pg_restore/psql will fail because junk_child.val now has a not null
constraint