Custom Domain; migration from 8.4 to 9.1 and COLLATE

This is a cross post from: http://dba.stackexchange.com/q/17609/2639

Just recently I upgraded from Postgresql 8.4.11 to 9.1.3. I used
pg_dump in the process. Now I'm getting an error:

> ERROR:  no collation was derived for column "vin" with collatable type citext
> HINT:  Use the COLLATE clause to set the collation explicitly.

This is a continuation of the [problem that I had
earlier](http://dba.stackexchange.com/q/17604/2639). It seems the fix
suggested in the Release Notes did not catch [custom
domains](http://www.postgresql.org/docs/9.1/interactive/sql-createdomain.html).
It seems as if the [CREATE
DOMAIN](http://www.postgresql.org/docs/8.3/interactive/sql-createdomain.html)
statement in 8.4 didn't even support the `COLLATE` clause.

This is how I created the `vin` type,

    CREATE DOMAIN inventory.valid_vin AS citext
      CHECK ( inventory.valid_vin( VALUE ) );

How do I best resolve this error?

--
Evan Carroll - me@evancarroll.com
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