can't sort by customer in line to invoice

[Aline (OpenERP)]

line to invoice (from Sales/Invoicing/Lines to Invoice)
      - bug when you sort by Customer (click on column header) -> you can fin traceback here under

reorganise group by : Salesman | Product Order | State

Traceback (most recent call last):
  File "/home/aline/openerp/trunk/server/bin/netsvc.py", line 489, in dispatch
    result = ExportService.getService(service_name).dispatch(method, auth, params)
  File "/home/aline/openerp/trunk/server/bin/service/web_services.py", line 586, in dispatch
    res = fn(db, uid, *params)
  File "/home/aline/openerp/trunk/server/bin/osv/osv.py", line 57, in wrapper
    return f(self, dbname, *args, **kwargs)
  File "/home/aline/openerp/trunk/server/bin/osv/osv.py", line 140, in execute
    res = pool.execute_cr(cr, uid, obj, method, *args, **kw)
  File "/home/aline/openerp/trunk/server/bin/osv/osv.py", line 130, in execute_cr
    return getattr(object, method)(cr, uid, *args, **kw)
  File "/home/aline/openerp/trunk/server/bin/osv/orm.py", line 1834, in search
    return self._search(cr, user, args, offset=offset, limit=limit, order=order, context=context, count=count)
  File "/home/aline/openerp/trunk/server/bin/osv/orm.py", line 4049, in _search
    order_by = self._generate_order_by(order, query)
  File "/home/aline/openerp/trunk/server/bin/osv/orm.py", line 4016, in _generate_order_by
    order_by_clause = self._generate_m2o_order_by(order_field, query)
  File "/home/aline/openerp/trunk/server/bin/osv/orm.py", line 3977, in _generate_m2o_order_by
    assert order_field_column._classic_write or getattr(order_field_column, 'store', False), "Many2one function/related fields must be stored to be used as ordering fields"
AssertionError: Many2one function/related fields must be stored to be used as ordering fields

[rvo(Open ERP) (rvo-openerp)]

Hello Aline,

It has been fixed in Addons3 branch.

revision-id: mra@mra-laptop-20101209125230-nrzbkf1ap0h7izf2
revno: 4738
branch-nick: trunk-dev-addons3

Thanks.