As our company practise is :
Q1: If the employee joined on 10/11/2011, his basic will devide according to the month day ( february /28, march/31, april /30 ).
RM2000/30days x 21days = RM1400 IF he took a day unpaid leave during November RM2000/26days x 1 day = ( RM80.77 )
RM 1400-80.77 = RM 1319.23 he will get for November salary
I also not sure is this method is valid / correct or not but it had been run in our company for 20 years++.
Q2: Yes, for unpaid leave taken, we devide by 26days irrespective of the month day. Yes, we are assume all the month are 26days, even in february, we also devide by 26days.
My superior told me, if completed 1 month service, should devide by 26days, if uncompleted due to first join or resign will devide according to month day.
Why different method, I think is becaused by completed or uncompleted month service.