title: TextField takes unicode in Django
body: <p>I am trying to save a string contains characters whose ordinal is not in range(128) into database. The field is declared as TextField in model and when I called the save() method, an exception was thrown: </p>
  
  <pre><code>File "/Library/Python/2.6/site-packages/django/db/models/base.py", line 434, in save self.save_base(using=using, force_insert=force_insert, force_update=force_update)
  File "/Library/Python/2.6/site-packages/django/db/models/base.py", line 500, in save_base rows = manager.using(using).filter(pk=pk_val)._update(values)
  File "/Library/Python/2.6/site-packages/django/db/models/query.py", line 491, in _update return query.get_compiler(self.db).execute_sql(None)
  File "/Library/Python/2.6/site-packages/django/db/models/sql/compiler.py", line 861, in execute_sql cursor = super(SQLUpdateCompiler, self).execute_sql(result_type)
  File "/Library/Python/2.6/site-packages/django/db/models/sql/compiler.py", line 717, in execute_sql sql, params = self.as_sql()
  File "/Library/Python/2.6/site-packages/django/db/models/sql/compiler.py", line 826, in as_sql val = field.get_db_prep_save(val, connection=self.connection)
  File "/Library/Python/2.6/site-packages/django/db/models/fields/subclassing.py", line 28, in inner return func(*args, **kwargs)
  File "/Library/Python/2.6/site-packages/django/db/models/fields/subclassing.py", line 28, in inner return func(*args, **kwargs)
  File "/Library/Python/2.6/site-packages/django/db/models/fields/__init__.py", line 276, in get_db_prep_save return self.get_db_prep_value(value, connection=connection, prepared=False)
  File "/Library/Python/2.6/site-packages/django/db/models/fields/subclassing.py", line 53, in inner return func(*args, **kwargs)
  File "/Library/Python/2.6/site-packages/django/db/models/fields/__init__.py", line 652, in get_db_prep_value value = self.get_prep_value(value)
  File "/Library/Python/2.6/site-packages/django/db/models/fields/__init__.py", line 647, in get_prep_value return self.to_python(value)
  File "/Library/Python/2.6/site-packages/django/db/models/fields/__init__.py", line 610, in to_python if not ansi_date_re.search(value):
  TypeError: expected string or buffer
  </code></pre>
  
  <p>Here is what I did:</p>
  
  <pre><code>str_unicode = str.encode('utf-8')
  m = MyModel.new(str = str_unicode)
  m.save()
  </code></pre>
  
  <p>So what should I do to enable the unicode compatibility?</p>
  
  <p><strong>Updated</strong>: I am currently using sqlite3 for development, python 2.6.1 and Django 1.2.4 on Mac</p>