Don't convert dictionary into a string representation

rest_framework/fields.py

@@ -90,6 +90,8 @@ class Field(object):
             return value
         elif hasattr(value, '__iter__') and not isinstance(value, (dict, basestring)):
             return [self.to_native(item) for item in value]
+        elif isinstance(value, dict):
+            return dict((k, self.to_native(v)) for k, v in value.items())
         return smart_unicode(value)
 
     def attributes(self):