BUG #2983: Nonsense error: "Table has type interval, but query expects interval"

The following bug has been logged online:

Bug reference: 2983
Logged by: David Flater
Email address: dave(at)flaterco(dot)com
PostgreSQL version: 8.2.2
Operating system: Linux
Description: Nonsense error: "Table has type interval, but query
expects interval"
Details:

-- Demo for interval defaulting to null bug in PostgreSql 8.2.2.
-- Simpler example with only 2 columns did not reproduce bug.
-- DWF, 20070209

create table data_sets (
index serial primary key,
name text not null,
original_name text,
station_id_context text,
station_id text,
lat double precision
check (lat >= -90 and lat <= 90),
lng double precision
check (lng >= -180 and lng <= 180),
timezone text not null,
country text,
units text not null
check (units = 'feet' or units = 'meters' or units = 'knots'
or units = 'knots^2'),
min_dir double precision
check (min_dir >= 0 and min_dir < 360),
max_dir double precision
check (max_dir >= 0 and max_dir < 360),
legalese text,
notes text,
comments text,
source text,
pedigree text,
restriction text not null,
date_imported date default current_date,
xfields text,
meridian interval hour to minute,
datumkind text,
datum double precision,
months_on_station smallint,
last_date_on_station date,
ref_index integer references data_sets,
min_time_add interval day to minute,
min_level_add double precision,
min_level_multiply double precision
check (min_level_multiply > 0),
max_time_add interval day to minute,
max_level_add double precision,
max_level_multiply double precision
check (max_level_multiply > 0),
flood_begins interval day to minute,
ebb_begins interval day to minute,
check ((lat is null and lng is null) or
(lat is not null and lng is not null)),
check ((datum is null and meridian is null) or
(datum is not null and meridian is not null)),
check (datum is not null or ref_index is not null)
) with oids;

-- This insert succeeds.
insert into data_sets (index, name, timezone, units, restriction, meridian,
datumkind, datum)
values (1,
'Generic Tide Reference Station',
'UTC0',
'meters',
'For testing only',
'0:00',
'Zulu',
0);

-- The following statement produces:
-- ERROR: attribute 21 has wrong type
-- DETAIL: Table has type interval, but query expects interval.
insert into data_sets (name, lat, lng, timezone, units, restriction,
ref_index)
values ('North Pole', 90, 0, 'UTC0', 'meters', 'For testing only',
1);

-- This insert succeeds (only difference is explicit null meridian).
insert into data_sets (name, lat, lng, timezone, units, restriction,
ref_index,
meridian)
values ('North Pole', 90, 0, 'UTC0', 'meters', 'For testing only', 1,
NULL);