Problem with polymorph mappers

tried to add alias to column in polymorph2.py in examples/polymorph and it doesn't work.

Here's a changes I made:

25c25
<    Column('primary_language', String(50)),
---
>    Column('primary_language', String(50), key='primaryLanguage'),
41c41
<         return "Engineer %s, status %s, engineer_name %s, primary_language %s" % (self.name, self.status, self.engineer_name, self.primary_language)
---
>         return "Engineer %s, status %s, engineer_name %s, primaryLanguage %s" % (self.name, self.status, self.engineer_name, self.primaryLanguage)
72c72
<                     engineers.c.primary_language, 
---
>                     engineers.c.primaryLanguage,

Full example is attached.

And it produces following error:

Traceback (most recent call last):
  File "C:\home\Vasily\sqlalchemy\sqlalchemy\examples\polymorph\polymorph3.py", line 114, in ?
    c = Company.get(1)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\mapper.py", line 245, in get
    return self.query.get(*ident, **kwargs)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\query.py", line 42, in get
    return self._get(key, ident, **kwargs)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\query.py", line 204, in _get
    return self._select_statement(statement, params=params, populate_existing=reload)[0](0)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\query.py", line 212, in _select_statement
    return self.instances(statement.execute(**params), **kwargs)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\query.py", line 167, in instances
    return self.mapper.instances(session=self.session, *args, **kwargs)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\mapper.py", line 388, in instances
    self._instance(session, row, imap, result, populate_existing=populate_existing)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\mapper.py", line 737, in _instance
    self.populate_instance(session, instance, row, identitykey, imap, isnew)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\mapper.py", line 760, in populate_instance
    prop.execute(session, instance, row, identitykey, imap, isnew)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\properties.py", line 807, in execute
    self._instance(session, row, imap, result_list)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\properties.py", line 837, in _instance
    return self.mapper._instance(session, row, imap, result_list)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\mapper.py", line 736, in _instance
    if self.extension.populate_instance(self, session, instance, row, identitykey, imap, isnew) is EXT_PASS:
  File "C:\home\Vasily\sqlalchemy\sqlalchemy\examples\polymorph\polymorph3.py", line 91, in populate_instance
    Engineer.mapper.populate_instance(session, instance, row, identitykey, imap, isnew, frommapper=mapper)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\mapper.py", line 757, in populate_instance
    row = frommapper.translate_row(self, row)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\mapper.py", line 752, in translate_row
    newrow[c](c) = newrow[c.key](c.key)
  File "C:\Python24\Lib\site-packages\sqlalchemy\util.py", line 189, in __getitem__
    return self.decorate[key](key)
  File "C:\Python24\Lib\site-packages\sqlalchemy\mapping\properties.py", line 816, in __getitem__
    return self.row[key](key)
  File "C:\Python24\Lib\site-packages\sqlalchemy\engine.py", line 867, in __getitem__
    return self.__parent._get_col(self.__row, key)
  File "C:\Python24\Lib\site-packages\sqlalchemy\engine.py", line 811, in _get_col
    rec = self.props[key.lower()](key.lower())
KeyError: 'primarylanguage'

It seems that problem is in file mapping/mapper.py lines 751-752:

        for c in tomapper.table.c:
            newrow[c](c) = newrow[c.key](c.key)

I changed it to

        for c in tomapper.table.c:
            newrow[c](c) = newrow[c.name](c.name)

And examples work. All other parts of sqlalchemy seem to still work. So that's perhaps a solution to shown problem.

Here's a diff of changes:

Index: lib/sqlalchemy/mapping/mapper.py
===================================================================
--- lib/sqlalchemy/mapping/mapper.py    (revision 1277)
+++ lib/sqlalchemy/mapping/mapper.py    (working copy)
@@ -749,7 +749,7 @@
         for c in self.table.c:
             newrow[c.key](c.key) = row[c](c)
         for c in tomapper.table.c:
-            newrow[c](c) = newrow[c.key](c.key)
+            newrow[c](c) = newrow[c.name](c.name)
         return newrow

     def populate_instance(self, session, instance, row, identitykey, imap, isnew, frommapper=None):

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