BUG #5315: Unlisted keyword WINDOW

The following bug has been logged online:

Bug reference:      5315
Logged by:
Email address:      sulfinu@gmail.com
PostgreSQL version: 8.4.2
Operating system:   Gentoo Linux
Description:        Unlisted keyword WINDOW
Details:

According to the official documentation
(http://www.postgresql.org/docs/8.4/interactive/sql-keywords-appendix.html),
the SQL reserved keyword WINDOW is totally uninteresting to PostgreSQL.

But in real life the parser has a different opinion. Just try this:
create table a (
window integer,
c varchar(20));

So, either correct the parser (is there any use for the word WINDOW in
Postgres?) or the documentation.