Eu sou muito novo no Django e desenvolvimento web. Aprendendo com o "Definitive guide to Django" ao criar o superusuário eu recebo o seguinte erro (OS mac10.8.2 & django1.4.3)

Would you like to create one now? (yes/no): yes
Traceback (most recent call last):
  File "manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/Library/Python/2.7/site-packages/django/core/management/__init__.py", line 443, in execute_from_command_line
    utility.execute()
  File "/Library/Python/2.7/site-packages/django/core/management/__init__.py", line 382, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/Library/Python/2.7/site-packages/django/core/management/base.py", line 196, in run_from_argv
    self.execute(*args, **options.__dict__)
  File "/Library/Python/2.7/site-packages/django/core/management/base.py", line 232, in execute
    output = self.handle(*args, **options)
  File "/Library/Python/2.7/site-packages/django/core/management/base.py", line 371, in handle
    return self.handle_noargs(**options)
  File "/Library/Python/2.7/site-packages/django/core/management/commands/syncdb.py", line 110, in handle_noargs
    emit_post_sync_signal(created_models, verbosity, interactive, db)
  File "/Library/Python/2.7/site-packages/django/core/management/sql.py", line 189, in emit_post_sync_signal
    interactive=interactive, db=db)
  File "/Library/Python/2.7/site-packages/django/dispatch/dispatcher.py", line 172, in send
    response = receiver(signal=self, sender=sender, **named)
  File "/Library/Python/2.7/site-packages/django/contrib/auth/management/__init__.py", line 73, in create_superuser
    call_command("createsuperuser", interactive=True, database=db)
  File "/Library/Python/2.7/site-packages/django/core/management/__init__.py", line 150, in call_command
    return klass.execute(*args, **defaults)
  File "/Library/Python/2.7/site-packages/django/core/management/base.py", line 232, in execute
    output = self.handle(*args, **options)
  File "/Library/Python/2.7/site-packages/django/contrib/auth/management/commands/createsuperuser.py", line 70, in handle
    default_username = get_default_username()
  File "/Library/Python/2.7/site-packages/django/contrib/auth/management/__init__.py", line 105, in get_default_username
    default_username = get_system_username()
  File "/Library/Python/2.7/site-packages/django/contrib/auth/management/__init__.py", line 85, in get_system_username
    return getpass.getuser().decode(locale.getdefaultlocale()[1])
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/locale.py", line 496, in getdefaultlocale
    return _parse_localename(localename)
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/locale.py", line 428, in _parse_localename
    raise ValueError, 'unknown locale: %s' % localename
ValueError: unknown locale: UTF-8

do guia definitivo para django estou mostrando um dos modelos.

from django.db import models
class Publisher(models.Model):
    name = models.CharField(max_length=30)
    address = models.CharField(max_length=50)
    city = models.CharField(max_length=60)
    state_province = models.CharField(max_length=30)
    country = models.CharField(max_length=50)
    website = models.URLField()

    def __str__(self):
        return self.name

    class Meta:
        ordering = ['name']

As configurações do banco de dados setting.py são: -

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2',
        'NAME': 'books',
        'USER': 'postgres',
        'PASSWORD': '******',
        'HOST': 'localhost',
        'PORT': '5432',
    }
}

O syncdb é executado:

Creating tables ...
Creating table auth_permission
Creating table auth_group_permissions
Creating table auth_group
Creating table auth_user_user_permissions
Creating table auth_user_groups
Creating table auth_user
Creating table django_content_type
Creating table django_session
Creating table django_site
Creating table books_publisher
Creating table books_author
Creating table books_book_authors
Creating table books_book

depois do sim para criar o superusuário, recebo o erro.