BUG #2848: information_schema.key_column_usage does not work

The following bug has been logged online:

Bug reference:      2848
Logged by:          Tony Marston
Email address:      tony@marston-home.demon.co.uk
PostgreSQL version: 8.2
Operating system:   Windows XP
Description:        information_schema.key_column_usage does not work
Details:

I have the following query:

SELECT key_column_usage.*,constraint_type
FROM information_schema.key_column_usage
LEFT JOIN information_schema.table_constraints USING
(table_schema,table_name,constraint_name)
WHERE table_schema='whatever' and table_name='whatever'
ORDER BY constraint_type, constraint_name, ordinal_position

This works when I am logged on as 'postgres', but if I try it after logging
on with a different username it fails with "ERROR: relation with OID 18635
does not exist".