Multi org category has to be updated manually

Hi

We have created a custom concurrent program in PURCHASING and attached 3 parameters (Start_date,End_date,PO_Number).Attached the Value set (PO_SRS_PO_NUmber) to the PO_NUMBER parameter but it was always throwing error "NO LIST of VALUES".

When verified the concurrent program the Multi org category value is showing null in table fnd_concurrent_program

After updating as below the values showed up.

UPDATE FND_CONCURRENT_PROGRAMS

SET multi_org_category='S'

where concurrent_program_name='CPDPOSPEC'

The Question is as we already have the MO:OPERATING UNIT and DEFAULT OPERATING UNIT setup at site level.Why did the value not populate automatically on the concurrent program define screen.