can't create a task with addon Project_time_sequence

No access to the code which solve the bug
Database with only the dependences Project, the error is

Client Traceback (most recent call last):
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\openerp\addons\web\common\http.py", line 180, in dispatch
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\openerp\addons\web\controllers\main.py", line 1161, in load
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\openerp\addons\web\controllers\main.py", line 1043, in fields_view_get
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\openerp\addons\web\common\openerplib\main.py", line 250, in proxy
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\openerp\addons\web\common\openerplib\main.py", line 117, in proxy
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\openerp\addons\web\common\http.py", line 611, in send

Server Traceback (most recent call last):
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\openerp\addons\web\common\http.py", line 592, in send
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\.\openerp\netsvc.py", line 360, in dispatch_rpc
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\.\openerp\service\web_services.py", line 572, in dispatch
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\.\openerp\osv\osv.py", line 167, in execute_kw
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\.\openerp\osv\osv.py", line 121, in wrapper
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\.\openerp\osv\osv.py", line 176, in execute
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\.\openerp\osv\osv.py", line 164, in execute_cr
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\openerp\addons\project\project.py", line 755, in fields_view_get
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\.\openerp\osv\orm.py", line 2124, in fields_view_get
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\.\openerp\osv\orm.py", line 2082, in apply_view_inheritance
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\.\openerp\osv\orm.py", line 2067, in apply_inheritance_specs
  File "C:\Program Files (x86)\OpenERP 6.1-1\server\.\openerp\osv\orm.py", line 1965, in raise_view_error
AttributeError: View definition error for inherited view 'project_time_sequence.view_task_form2' on model 'project.task': Element '<xpath expr="//page[@string='Delegations']">' not found in parent view '%(parent_xml_id)s'