BUG #6124: overlaps

The following bug has been logged online:

Bug reference:      6124
Logged by:          Ludek Bouska
Email address:      ludek@bouska.info
PostgreSQL version: 8.3.7
Operating system:   FreeBSD 7.2-RELEASE-p3
Description:        overlaps
Details:

script
select ('20110720'::date,'20110721'::date) overlaps
('20110721'::date,'20110721'::date)
gives false.

It is necessary to make it as
select ('20110720'::date,'20110721'::date+'1 day'::Interval) overlaps
('20110721'::date,'20110721'::date)
for the 20110721 be realy overlapped.