Default gin operator class of jsonb failing with index row size maximum reached

Hi all,

While doing some tests with jsonb, I found a failure as told in $subject:
=# create table data_jsonb (data jsonb);
CREATE TABLE
=# insert into data_jsonb ... tuple in the script attached
INSERT 1
=# create index data_index on data_jsonb using gin(data);
ERROR:  54000: index row size 1808 exceeds maximum 1352 for index "data_index"
LOCATION:  GinFormTuple, ginentrypage.c:110
=# create index data_index2 on data_jsonb using gin (data jsonb_hash_ops);
CREATE INDEX

The data creating the failure is a tuple in a dump of geonames
(http://www.geonames.org/export/), listing some geographical data, and
it is caused by some arabic characters it seems used to provide
translations for a given geographical location. Encoding of the
database on which I have done the tests is UTF-8. Japanese, Chinese
equivalents were working fine btw with this operator.

Documentation of jsonb tells that jsonb documents should be kept at a
reasonable size to reduce lock contention, but there is no mention of
size limitation for indexes:
http://www.postgresql.org/docs/devel/static/datatype-json.html

A test case is attached, note as well that only the default gin
operator class is failing, jsonb_hash_ops worked well.
Regards,
--
Michael