BUG #2219: bug in 12000 rows update

The following bug has been logged online:

Bug reference: 2219
Logged by: Ricardo Solanilla
Email address: abasoft(at)ciudad(dot)com(dot)ar
PostgreSQL version: 8.0
Operating system: Windows XP
Description: bug in 12000 rows update
Details:

i has report this bug earlier (ref. 2210) but i've news. The problem
dissapear if i execute the update query with less rows ..
begin transaction;
... where id > 100 and id <= 1000
commit;

begin transaction;
... where id > 1001 .. and so
commit;

and i've noted that without begin transaction and commit the group of querys
doesn't work (in pgadmin iii).

the problem is in a specific database, then i only can offer send my
database to anybody who like it, i cannot make a case to show the bug.