BUG #3700: initdb could not find suitable encoding for locale "Polish_Poland.1250"

The following bug has been logged online:

Bug reference: 3700
Logged by: Marek Romanowski
Email address: marek(dot)romanowski(at)gmail(dot)com
PostgreSQL version: 8.3-beta1
Operating system: Windows XP Professional
Description: initdb could not find suitable encoding for locale
"Polish_Poland.1250"
Details:

I've installed 8.2 yesterday and everything was ok,
so I think it's some kind of regression bug.

Second run was with -E LATIN2 option, so encoding was
given clearly, database was initialized, but some
warnings about encoding showed up too.

$ ./initdb -D "c:\java\pgdata-8.3"
The files belonging to this database system will be owned by user
"efigence".
This user must also own the server process.

The database cluster will be initialized with locale Polish_Poland.1250.
could not determine encoding for locale "Polish_Poland.1250": codeset is
"CP1250"
initdb: could not find suitable encoding for locale "Polish_Poland.1250"
Rerun initdb with the -E option.
Try "initdb --help" for more information.

$ ./initdb -D "c:\java\pgdata-8.3" -E LATIN2
The files belonging to this database system will be owned by user
"efigence".
This user must also own the server process.

The database cluster will be initialized with locale Polish_Poland.1250.
could not determine encoding for locale "Polish_Poland.1250": codeset is
"CP1250"
initdb: could not find suitable text search configuration for locale
"Polish_Poland.1250"
The default text search configuration will be set to "simple".

creating directory c:/java/pgdata-8.3 ... ok
creating subdirectories ... ok
selecting default max_connections ... 100
selecting default shared_buffers/max_fsm_pages ... 32MB/204800
creating configuration files ... ok
creating template1 database in c:/java/pgdata-8.3/base/1 ... ok
initializing pg_authid ... ok
initializing dependencies ... ok
creating system views ... ok
loading system objects' descriptions ... ok
creating conversions ... ok
creating dictionaries ... ok
setting privileges on built-in objects ... ok
creating information schema ... ok
vacuuming database template1 ... ok
copying template1 to template0 ... WARNING: could not determine encoding
for locale "Polish_Poland.1250": codeset is "CP1250"
DETAIL: Please report this to <pgsql-bugs(at)postgresql(dot)org>.
ok
copying template1 to postgres ... WARNING: could not determine encoding for
locale "Polish_Poland.1250": codeset is "CP1250"
DETAIL: Please report this to <pgsql-bugs(at)postgresql(dot)org>.
ok

WARNING: enabling "trust" authentication for local connections
You can change this by editing pg_hba.conf or using the -A option the
next time you run initdb.

Success. You can now start the database server using:

"c:\Program Files\PostgreSQL\8.3-beta1\bin\postgres" -D
"c:/java/pgdata-8.3"
or
"c:\Program Files\PostgreSQL\8.3-beta1\bin\pg_ctl" -D
"c:/java/pgdata-8.3" -l logfile start