This is my situation:

An employee fills in his timesheet and he submits it to the manager, so the manager can approve or refuse the timesheet. But in my situation, sometimes it is not the manager who has to judge the timesheets but the customer has to judge them. Right now the customer can view the timesheets by using the portal for OpenERP but I would also like to give portal users the possibility to approve or refuse the timesheet of the employees. How can I make this possible?