transport_account_id -> field exist in the model 'project.events'

-> 'transport_account_id': fields.many2one('account.account','Tranport Account'),

Code:

from openerp.osv import fields, osv
from openerp.tools.translate import _

class project_events_configuration(osv.osv_memory):
    _name = 'project.events.config.settings'
    _inherit = 'res.config.settings'

    _columns = {
        'default_transport_account_id': fields.many2one('account.account','Tranport Account', required=True, default_model='project.events'),
    }

XML

<record id="view_config_events_settings" model="ir.ui.view">
            <field name="name">project events settings</field>
            <field name="model">project.events.config.settings</field>
            <field name="priority" eval="20"/>
            <field name="arch" type="xml">
                <form string="Configure Project" version="7.0" class="oe_form_configuration">
                    <header>
                        <button string="Apply" type="object" name="execute" class="oe_highlight"/>
                        or
                        <button string="Cancel" type="object" name="cancel" class="oe_link"/>
                    </header>
                    <separator string="Event Management"/>
                    <group>
                        <div name="other_cofing">
                            <div>
                                <label for="default_transport_account_id"/>
                                <field name="default_transport_account_id" class="oe_inline"/>
                            </div>
                        </div>
                    </group>                 
                </form>
            </field>
        </record>

When saving the default value I get a the following error:

Traceback (most recent call last):
  File "/opt/openerp/server/8.0/upstairs/openerp/http.py", line 369, in dispatch
    response["result"] = self._call_function(**self.params)
  File "/opt/openerp/server/8.0/upstairs/openerp/http.py", line 230, in _call_function
    return checked_call(self.db, *args, **kwargs)
  File "/opt/openerp/server/8.0/upstairs/openerp/service/model.py", line 113, in wrapper
    return f(dbname, *args, **kwargs)
  File "/opt/openerp/server/8.0/upstairs/openerp/http.py", line 227, in checked_call
    return self.endpoint(*a, **kw)
  File "/opt/openerp/server/8.0/upstairs/openerp/http.py", line 570, in __call__
    return self.method(*args, **kw)
  File "/opt/openerp/server/8.0/upstairs/openerp/http.py", line 273, in response_wrap
    response = f(*args, **kw)
  File "/opt/openerp/env/8.0/upstairs/web/addons/web/controllers/main.py", line 1230, in call_button
    action = self._call_kw(model, method, args, {})
  File "/opt/openerp/env/8.0/upstairs/web/addons/web/controllers/main.py", line 1218, in _call_kw
    return getattr(request.registry.get(model), method)(request.cr, request.uid, *args, **kwargs)
  File "/opt/openerp/server/8.0/upstairs/openerp/addons/base/res/res_config.py", line 509, in execute
    ir_values.set_default(cr, SUPERUSER_ID, model, field, config[name])
  File "/opt/openerp/server/8.0/upstairs/openerp/addons/base/ir/ir_values.py", line 248, in set_default
    'value': pickle.dumps(value),
  File "/usr/lib/python2.7/pickle.py", line 1374, in dumps
    Pickler(file, protocol).dump(obj)
  File "/usr/lib/python2.7/pickle.py", line 224, in dump
    self.save(obj)
  File "/usr/lib/python2.7/pickle.py", line 331, in save
    self.save_reduce(obj=obj, *rv)
  File "/usr/lib/python2.7/pickle.py", line 419, in save_reduce
    save(state)
  File "/usr/lib/python2.7/pickle.py", line 286, in save
    f(self, obj) # Call unbound method with explicit self
  File "/usr/lib/python2.7/pickle.py", line 649, in save_dict
    self._batch_setitems(obj.iteritems())
  File "/usr/lib/python2.7/pickle.py", line 663, in _batch_setitems
    save(v)
  File "/usr/lib/python2.7/pickle.py", line 331, in save
    self.save_reduce(obj=obj, *rv)
  File "/usr/lib/python2.7/pickle.py", line 401, in save_reduce
    save(args)
  File "/usr/lib/python2.7/pickle.py", line 286, in save
    f(self, obj) # Call unbound method with explicit self
  File "/usr/lib/python2.7/pickle.py", line 562, in save_tuple
    save(element)
  File "/usr/lib/python2.7/pickle.py", line 300, in save
    self.save_global(obj)
  File "/usr/lib/python2.7/pickle.py", line 748, in save_global
    (obj, module, name))
PicklingError: Can't pickle <class 'openerp.osv.orm.account.account'>: it's not found as openerp.osv.orm.account.account