[Dbmail] postgresql add_header_tables.pgsql missing references table

[Joe Love]

I upgraded from 2.0.7, and found during my upgrade that the table for 
referencesfield was missing.  I added it manually, but I'd like to know 
if it's correct.  (It seems to work.)

The following is the lines I added to the add_header_tables.pgsql file 
in order to get this table.

CREATE SEQUENCE dbmail_referencesfield_idnr_seq;
CREATE TABLE dbmail_referencesfield (
       physmessage_id  INT8 NOT NULL
                       REFERENCES dbmail_physmessage(id)
                       ON UPDATE CASCADE ON DELETE CASCADE,
       id              INT8 DEFAULT 
nextval('dbmail_referencesfield_idnr_seq'),
       referencesfield VARCHAR(255) NOT NULL DEFAULT '',
       PRIMARY KEY (id)
);
CREATE UNIQUE INDEX dbmail_referencesfield_1 ON 
dbmail_referencesfield(physmessage_id, id);

Thanks,
-Joe