diff --git a/addons/hr_payroll/hr_payroll.py b/addons/hr_payroll/hr_payroll.py
index 5fad62a0b03..d03074f3273 100644
--- a/addons/hr_payroll/hr_payroll.py
+++ b/addons/hr_payroll/hr_payroll.py
@@ -280,7 +280,7 @@ class hr_payslip(osv.osv):
             \n* When user cancel payslip the status is \'Rejected\'.'),
         'line_ids': one2many_mod2('hr.payslip.line', 'slip_id', 'Payslip Lines', readonly=True, states={'draft':[('readonly',False)]}),
         'company_id': fields.many2one('res.company', 'Company', required=False, readonly=True, states={'draft': [('readonly', False)]}, copy=False),
-        'worked_days_line_ids': fields.one2many('hr.payslip.worked_days', 'payslip_id', 'Payslip Worked Days', required=False, readonly=True, states={'draft': [('readonly', False)]}),
+        'worked_days_line_ids': fields.one2many('hr.payslip.worked_days', 'payslip_id', 'Payslip Worked Days', copy=True, required=False, readonly=True, states={'draft': [('readonly', False)]}),
         'input_line_ids': fields.one2many('hr.payslip.input', 'payslip_id', 'Payslip Inputs', required=False, readonly=True, states={'draft': [('readonly', False)]}),
         'paid': fields.boolean('Made Payment Order ? ', required=False, readonly=True, states={'draft': [('readonly', False)]}, copy=False),
         'note': fields.text('Internal Note', readonly=True, states={'draft':[('readonly',False)]}),
@@ -322,7 +322,6 @@ class hr_payslip(osv.osv):
         mod_obj = self.pool.get('ir.model.data')
         for payslip in self.browse(cr, uid, ids, context=context):
             id_copy = self.copy(cr, uid, payslip.id, {'credit_note': True, 'name': _('Refund: ')+payslip.name}, context=context)
-            self.compute_sheet(cr, uid, [id_copy], context=context)
             self.signal_workflow(cr, uid, [id_copy], 'hr_verify_sheet')
             self.signal_workflow(cr, uid, [id_copy], 'process_sheet')