Hello to all, I have come across a weird problem in OpenERP-7 server. I have uploaded the error details below:

Client Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.7/openerp/addons/web/http.py", line 204, in dispatch
    response["result"] = method(self, **self.params)
  File "/usr/lib/pymodules/python2.7/openerp/addons/web/controllers/main.py", line 867, in authenticate
    req.session.authenticate(db, login, password, env)
  File "/usr/lib/pymodules/python2.7/openerp/addons/web/session.py", line 115, in authenticate
    uid = self.proxy('common').authenticate(db, login, password, env)
  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 103, in send
    raise xmlrpclib.Fault(openerp.tools.ustr(e), formatted_info)


Server Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.7/openerp/addons/web/session.py", line 89, in send
    return openerp.netsvc.dispatch_rpc(service_name, method, args)
  File "/usr/lib/pymodules/python2.7/openerp/netsvc.py", line 292, in dispatch_rpc
    result = ExportService.getService(service_name).dispatch(method, params)
  File "/usr/lib/pymodules/python2.7/openerp/service/web_services.py", line 433, in dispatch
    return fn(*params)
  File "/usr/lib/pymodules/python2.7/openerp/service/web_services.py", line 444, in exp_authenticate
    res_users = pooler.get_pool(db).get('res.users')
  File "/usr/lib/pymodules/python2.7/openerp/pooler.py", line 49, in get_pool
    return get_db_and_pool(db_name, force_demo, status, update_module)[1]
  File "/usr/lib/pymodules/python2.7/openerp/pooler.py", line 33, in get_db_and_pool
    registry = RegistryManager.get(db_name, force_demo, status, update_module)
  File "/usr/lib/pymodules/python2.7/openerp/modules/registry.py", line 192, in get
    update_module)
  File "/usr/lib/pymodules/python2.7/openerp/modules/registry.py", line 218, in new
    openerp.modules.load_modules(registry.db, force_demo, status, update_module)
  File "/usr/lib/pymodules/python2.7/openerp/modules/loading.py", line 435, in load_modules
    model._register_hook(cr)
  File "/usr/lib/pymodules/python2.7/openerp/addons/base_action_rule/base_action_rule.py", line 201, in _register_hook
    model_obj.create = self._wrap_create(model_obj.create, model)
AttributeError: 'NoneType' object has no attribute 'create'

Hopes for suggestion

Regards