Locale support on Mac OS X

Hi,
I'm trying to enable italian locale support on a Mac OS X host.
I run the initdb command with the following parameters (among others):
--encoding=UNICODE --locale=it_IT.UTF-8
then I created a new test database

test_locale=# \d test_sort
Table "public.test_sort"
Column | Type | Modifiers
------------+------+-----------
text_field | text |

test_locale=# select * from test_sort;
text_field
------------
a
b
c
d
e
è
é
à
A
(9 rows)

But the order by clause yields the wrong results

test_locale=# select * from test_sort order by text_field;
text_field
------------
A
a
b
c
d
e
à
è
é
(9 rows)

Further points:
- The sort command gives the same (wrong) results.
- GUI (Cocoa) applications give the expected sort.

Any clues? Should I assume that if sort does not give the expected
result, postgresql will not be different?

Thank you in advance

--
Giorgio Valoti
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