Planning Calendar - requirements should be generated on hoildays

Hi all,

I have a public hoilday mainaitained in SCAL - Say 31st aug 2009 - Monday . my requirement is when MRP runs then the F material should gernate VSA ( requirement ) on a holiday.

I have created a planning calendar with period as every monday ( As delivery) and marled check box - do not displace holiday , and i have checked the period is caluclating taking 31st Aug as working day

I material master i have maintianed Lot size as "planning acording to planning calendar " and i have maintained planning claendar in MRP view

When i ran MRP , the reuqirment is genrated either on 28 aug or 2 aug based on backward / scheuling

Can anybody please let me know how to generate requirements on holidays.

Thanks

Vinod