Project - Problem with adding custom field

Hi,

I tried do add custom field to project, but without success.
I am using version 6.2dev-20121122-000101
You can see error report:

Client Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.7/openerp/addons/web/http.py", line 192, in dispatch
    response["result"] = method(self, **self.params)
  File "/usr/lib/pymodules/python2.7/openerp/addons/web/controllers/main.py", line 1242, in call_kw
    return self._call_kw(req, model, method, args, kwargs)
  File "/usr/lib/pymodules/python2.7/openerp/addons/web/controllers/main.py", line 1204, in _call_kw
    return getattr(req.session.model(model), method)(*args, **kwargs)
  File "/usr/lib/pymodules/python2.7/openerp/addons/web/session.py", line 42, in proxy
    result = self.proxy.execute_kw(self.session._db, self.session._uid, self.session._password, self.model, method, args, kw)
  File "/usr/lib/pymodules/python2.7/openerp/addons/web/session.py", line 30, in proxy_method
    result = self.session.send(self.service_name, method, *args)
  File "/usr/lib/pymodules/python2.7/openerp/addons/web/session.py", line 105, in send
    raise xmlrpclib.Fault(openerp.tools.exception_to_unicode(e), formatted_info)

Server Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.7/openerp/addons/web/session.py", line 91, in send
    return openerp.netsvc.dispatch_rpc(service_name, method, args)
  File "/usr/lib/pymodules/python2.7/openerp/netsvc.py", line 361, in dispatch_rpc
    result = ExportService.getService(service_name).dispatch(method, params)
  File "/usr/lib/pymodules/python2.7/openerp/service/web_services.py", line 596, in dispatch
    res = fn(db, uid, *params)
  File "/usr/lib/pymodules/python2.7/openerp/osv/osv.py", line 167, in execute_kw
    return self.execute(db, uid, obj, method, *args, **kw or {})
  File "/usr/lib/pymodules/python2.7/openerp/osv/osv.py", line 121, in wrapper
    return f(self, dbname, *args, **kwargs)
  File "/usr/lib/pymodules/python2.7/openerp/osv/osv.py", line 176, in execute
    res = self.execute_cr(cr, uid, obj, method, *args, **kw)
  File "/usr/lib/pymodules/python2.7/openerp/osv/osv.py", line 164, in execute_cr
    return getattr(object, method)(cr, uid, *args, **kw)
  File "/usr/lib/pymodules/python2.7/openerp/addons/base/ir/ir_model.py", line 340, in create
    self.pool.get(vals['model']).__init__(self.pool, cr)
  File "/usr/lib/pymodules/python2.7/openerp/osv/orm.py", line 1071, in __init__
    assert self._rec_name in self._columns.keys() + ['id'], "Invalid rec_name %s for model %s" % (self._rec_name, self._name)
AssertionError: Invalid rec_name name for model project.project