BUG #3413: character string or multibyte character to "char"

The following bug has been logged online:

Bug reference: 3413
Logged by: Toru SHIMOGAKI
Email address: shimogaki(dot)toru(at)oss(dot)ntt(dot)co(dot)jp
PostgreSQL version: 8.2.4
Operating system: Red Hat Enterprise Linux AS4
Description: character string or multibyte character to "char"
Details:

When a character string or a multibyte character is inserted to "char"
column, no error occurs. Is this a bug? Should it be checked as "not single
character" in charin(), charrecv() and charout()?

Anyway, I can't find any spec descriptions in the following document;
http://www.postgresql.org/docs/8.2/static/datatype-character.html

Best regards,

----

postgres=# select version();
version
----------------------------------------------------------------------------
-----------------------
PostgreSQL 8.2.4 on i686-pc-linux-gnu, compiled by GCC gcc (GCC) 3.4.6
20060404 (Red Hat 3.4.6-3)
(1 row)

postgres=# create table test(flag "char");
CREATE TABLE
postgres=# \d test
Table "public.test"
Column | Type | Modifiers
--------+--------+-----------
flag | "char" |

postgres=# insert into test values('a');
INSERT 0 1
postgres=# insert into test values('bb');
INSERT 0 1
postgres=# insert into test values('eeeee');
INSERT 0 1
postgres=# insert into test values('');
INSERT 0 1
postgres=# select * from test;
flag
------
a
b
e

(4 rows)